US1734981A - Means for transporting concrete - Google Patents

Description

Nov. 12, 1929. E s, mpg 1,734,981

MEANS FOR TRANSPORTING CONCRETE Filed May "3, 192,9

F/GJ.

F/GJ.

/wzwfss I 4 v50 A further objection Patented Nov. 12, 1929 UNITED STATES PATENT oFFlcE EARLE S. PHILIPS, F KENNETT SQUARE, IPENNSYLVANIA, ASSIGNOR TO AMERICAN ROAD MACHINERY COMPANY, 0F KENNETT SQUARE, PENNSYLVANIA, A CORPORA- TION OF DELAWARE MEANS FOR TRANSPOR'IIING CONCRETE Applicationled May 3, 1929. Serial No. 360,069.

This invention relates to means for transporting concrete and more particularly to a motor-driven truck Which is adapted to mix or maintain mixed a charge of Wet concrete during transportation.

i Heretofore it has been attempted to mix concrete at central mixing plants and transport the concrete from such plants to the place of use. At first, ordinary dump trucks were used but it was found that in a very short time after loading, and probably due to vibration of the truck during transportation. the aggregate, being heavier than the more liquid portions of the mix, would settle on the bottom of the truck, forming a hard compact mass which Wasremovable only with difiiculty and Which necessitated a re-mixing of the concrete at the point of use.

To avoid these difficulties, various trucks 2G have been designed having revolving tanks thereon. In one form of this construction, the revolving tank is provided with a plurality of inwardly extending blades which are designed to churn the concrete, thus eifectively maintaining a proper mixture. Such construction has been found impractical, however, by reason of the fact that the concrete collects and solidifies at the junction of the blades with the Walls of the cylinder, coating the same so as to render them substantially ineffective and preventing the ready removal of the mixed concrete.

To avoid this objectionable feature resulting from the use of blades, attempts have also been made to .use smooth Walled cylindrical tanks concentric With the axis of rotation. In such tanks, relatively little mixing occurs. the tanks being only effective to a relatively slight degree to maintain mixed yan already thoroughly mixed concrete, but being inoperative to actually mix the unmixed ingredients to form a finished -concrete. Conse quently, the use of such tanks necessitates 'complete mixing prior to the filling of the tank, a process more costly than that resulting when tanks with blades are used, since if blades are used the unmixed ingredients may be dumped into the tank and thorough mixing will take place during the transportation.

to the .use of such smooth Walled tanks of circular cross section is the necessity of having the tank substantially more than half full in order to even maintain mixed an already mixed concrete. It is found that if the tank is less than half full substantially no mixing will occur. Furthermore, in these smooth Walled tanks in order to obtain any mixing a more vigorous rotation is necessary, the result of which is rapid Wearing of the Walls of the tank. If blades are used, a more thorough mixing takes place with less vigorous rotation and the blades, Which are relatively cheap and may be replaced, take up the wear rather than the Walls of the tank.

Rotary tanks of the character described are generally provided With discharge openings in the rear end walls thereof. Upon opening a sliding gate or the like, when the walls of the tank are smooth it is found that the concrete gushes out in an uncontrollable and objectionable manner which renders impossible thc efficient use of chutes since the concrete tends to spill over the sides thereof. On the other hand, when blades are used, they have heretofore presented obstructions to the discharge of the concrete.

In my prior application ASerial No. 305,- 338, filedt September 12, 1928, there is disclosed a tank overcoming the difficulties and objections referred to above in that mixing is accomplished Without the accumulation of concrete at\the junction of the fins with the Walls of the tank and proper and controlled discharge through the discharge opening is effected.

It is the object of the present invention' to improve upon the construction disclosed in my said prior application by providing means for securing a longitudinal back and forth movementof the contents of the tank during its rotation, so as to effect more ycomplete mixture or maintenance of mixture ofthe contents. Y

This and other more specific objects and their accomplishment will be apparent from the following description read in connection with the accompanying drawing, in which:

Fig. 1 is a plan view of a tank constructed in accordance with my invention;

Fig. 2 is a side elevation of the same; and

Fig. 3 is a section looking toward the front end of the tank taken on a plane indicated by line 3 3 of Fig. 2. y

The chassis o a motor truck is indicated at 2. This chassis carries upright supporting brackets 4 ofthe type disclosed in my prior application in which is rotatably mounted *he front and rear trunnions of a rotary tank 6 driven by means of a separate driving motor 7 or by suitable transmission mechanism from the driving motor of the truck. The tank. at its rear end, is provided with a discharge opening 8 at the bottom thereof and has a suitable charging opening 10 in its partly in section i l top. Both of these openings are adapted to be normally closed by suitable covers, not

' `shown.

At the bottom of the tank are positioned a plurality of ns 12 converging as shown toward the discharge opening in the same manner as the corresponding tinsof my prior application. These tins are spaced from the walls of the tank, being supported by downwardly extending bolts suitably secured in the walls of the tank. The spacing of fins 12 increases from the rear to the front of .the tank, as will be apparent from Fig. 2. The; fins 12 do not extend radially but in substantially the same direction. In other words, the sections formed by a plane transverse to the axis of rotation would be parallel.

Oppositely disposed with respect to tins 12 and at the top of the tank are similar fins 16 supported by and spaced from the wall of the tank by bolts 18. These fins converge toward the front of the tank, as will be clear from an examination of Fig. 1. The spacing of the tins from the walls of the tank increases from the front to the rear of the tank, or opposite to the spacing of the previously discussed fins 12. Fins 16, like lins 12, do not extend radially but in the same general direction.

By reason of the convergence of fins 12 toward the discharge opening, when the gate covering that opening is raised, the concrete outwardly of the tins is not free to rush crosswise of the opening but an even and controlled iiow of the concrete outwardly from between the 'tins is maintained. Accordingly, the discharge will flow down a chute.

During the rotation of the tank with the mixture therein, the opposite convergence of fins 12 and 16 will provide, in addition to the ordinary and effective mixing action, an oscillating flow of the mixture between the ends of the tank. As a result, admixture is more readily effected if unmixed constituents are placed in the tank, or more readily maintained after complete mixture.

The spacing of the tins prevents the retention of concrete along the line of junction between the iinsand the wall of the tank.

The blades, however, retain their complete effectiveness in contributing to the production and maintenance of the proper mixture.

Vhat I claim and desire to protect by Letters Patent is:

1. Means ior transporting and mixing concrete comprising a vehicle, a rotary tank mounted on the vehicle, means for rotating the tank, and at least two pairs of mixing tins oppositely disposed within the tank and extending along the inner walls thereof, the tins of one pair converging towards the front of the tank and the fins of the other pair converging towards the rear thereof.

2. Means for transporting and mixing concrete comprising a vehicle, a rotary tank mounted on the Vehicle, means for rotating the tank, and at least two pairs of mixing tins oppositely disposed within the tank andextending along the inner walls thereof in spaced relation thereto, the tins of one pair converging towards the front of the tank and the fins of the other pair converging towards the rear thereof.

3. Means for transporting and mixingconcrete comprising a vehicle, a rotary ltank mounted on the vehicle, meansfor rotating the tank. and at least two pairs of mixing tins oppositely disposed within the tank and extending along the inner walls thereof, the Iins of one pair converging towards the front of the tank and the tins of the other pair converging towards t-he rear thereof, the members of each pair extending inwardly from the walls of the tank in approximately the same direction.

4. Means for transporting and mixing concrete comprising a vehicle, a rotary tank mounted on the vehicle, means for rotating the tank, and at least two pairs of mixing fins oppositely disposed within the tank and extending along the inner walls thereof in spaced relation thereto, the fins of one pair converging towards the front of the tank and the tins of the other pair converging towards the rear thereof, the members of each pair extending inwardly from the walls of the tank in approximately the same direction.

5. Means for transporting and mixing concrete comprising a vehicle, a rotary tank mounted on the vehicle, means for rotating the tank, and at least two pairs of mixing ins oppositely disposed within the tank and extending along the innerwalls thereof in spaced relation thereto, the fins of one pair converging towards the front of the tank and the fins of the other pair convergin towards the rear thereof, the fins being space from the `walls of the tank to a greater extent at one end than at the other.

6. Means for transporting and mixing concrete comprising a vehicle, a rotary tank mounted on the vehicle, means for rotating the tank, and at least two pairs of mixing fins oppositely disposed within the tank and extending along theinner walls thereof, said. tank having a discharge opening at one end thereof, the ns of one pair converging towards the opening, and the fins of the other pair converging towards the other end of the tank.

7. Means for transporting and mixing concrete comprising a vehicle, a rotary tank mounted on the vehicle, means for rotating the tank, and at least two pairs of mixino' fins oppositely disposed within the tank an extending along the inner Walls thereof in spaced relation thereto, said tank having-na discharge opening at one end thereof, the s of one pair converging Atowards the opening, and the ns of the other pair converging towards the other end of the tank.

In testimony of which invention, I have hereunto set my hand, at Kennett Square, Pa., on this 25th day of April, 1929.

EARLE S. PHILIPS.

Images