US2620541A - Machine for molding concrete blocks - Google Patents

Description

Dec. 9, 1952 DAVlEs EI-AL 2,620,541

MACHINE FOR MOLDING CONCRETE BLOCKS Filed Nov. 25, 1949 3 Sheets-Sheet l JNV ENTOR. M1 Zes. Dawes and 1952 M. DAVIES ETAL 2,620,541

' MACHINE FOR MOLDING CONCRETE BLOCKS Filed Nov. 25, 1949 s Shets-Sheet 2 INVENTOR. Mi Zes Davies and Dec. 9, 1952 M. DAVIES ETAL 2,620,541

- MACHINE FOR MOLDING CONCRETE BLOCKS Filed Nov. 25, 1949 3 Sheets-Sheet 5 a v i INVEZNTOR. M1285 Dc was and Patented Dec. 9, 1952 OFFICE OLDING CONCRETE MAGHINEv FOR M BL OCKS MilesiDavies 'andFred Neth, Vancouver, Wash;

Application November 25, 1949; SerialtN0. 129, 38.8'

(Cl.v 25-41) 3 Claims. I Qur. invention-.relatesto. concrete blockformin machines and. to; animprovement. in. the art. of trowelingsaidblocks to: produce a smoothfinish thereon.v

One of the principalobjectsof our invention is to provide a. machine witha box-like mold having sides-andendsbut no bottom. A pallet un.- derlies'and seals the bottom of said mold. Said mold iscarried at the endsof pairs of elongated spring element-s whichare subject to fiexure along a path which-is substantially vertical. Said mold isv provided with vibrator means for partially supporting it and for shaking it rapidly. Thevib-rator means is provided with pivotal joints so that the movement of said mold is limited to the path defined by the flexure of said spring elements. Ejecting mean-sis provided for said mold, which is operable to discharge formed blocks through the open bottom of said mold along a path substantially parallel with that defined by the flexureof said spring elements, and the vibration is continued while said blocks are being ejected so as to cause the sides and ends of said mold to trowel the abutting faces of said concrete blocks, previously formed in said mold, while they are being ejected therefrom, to produce a smooth finish thereon.

Further and. other details of our invention are further described in connection with the accompanying drawings, in which:

Fig. 1 is a front elevation of a machine embodying our invention, with the motor drive. therefor shown in dotted lines;

Fig. 2-is an end elevation of said machine, with portionsshown broken away to disclose the driving means which would otherwise be concealed;

Fig. 3. is an enlarged detailed view of the mold box of said machine, its supporting springs and a portion of the power driven vibrating means, themovement of said mold box being diagrammatically depicted by double-ended arrows applied to said drawing; and

Fig.4 is. an enlarged sectional view taken on the line 44 in Fig. 3.

The general details of our machine are similar to the machine. illustratedin the co-pending application for Letters Patent filed December 6, 1948., by Russell B. Nelson, Miles Davies, and Fred Neth, zbearing Serial No. 63.812 and entitled Method of and. Machine for Making Concrete Blocks. Reference, is made. to said application for. the general details of. said machine and the method of-operationthereoi.

Sufii'ce it to say that aconcrete block making machine. embodying the: features of our invention comprises a; rectangular. frame. Projecting from the front of. said frame are two pairs of base. members including an upper pair 2 and a lower pair 3. Said base members have vertically alined eyes formed therein for receivingthetubular sleeves whichreciprocate therein. Thelower endsof. said. sleeves. are joined together below the lower. base member 3'. by horizontal toggle beam 5, which is secured to said sleeves by bolts. The toggle beam is supportedat its center upon the upper end of, apiston rod 6., which issecured thereto, andat. each endby a toggle mechanism as is shown in Figure 2. It is this toggle mechanism which actuates a pressure head 44 to compress the mold contents during casting as will hereinafter be described. The opposite endofthe piston rod is connected to a piston. which is movable vertically within a double-acting hydraulic stripper. cylinder 1. The stripper cylinder is secured. to an H-shapedbracket 8, which projects from the front of said frame. The bracketB isformed withlaterally projecting flanges 9 on its upper edge to provide support for the upstanding pedestals I0 which. are secured thereto. A shoulder II. is. formed about each of. said pedestals intermediate. the ends thereof. Removable bumpers l2. each have a hollow end which slidably engages the upper .end of the pedestals. A shoulder I3 is formed intermediate. the endsof said bumpers. Coil springs l4 encircle the engaged portions of said pedestals and bumpers, and. abut at their ends against the opposing faces of sai'dshoulders. In therelaxed position. of said springs. the, telescoping ends of the pedestals. and bumpers are spaced apart, and may bemoved together by compressing the coil springs I4. The upper endsof the bumpers are arranged. to contact the toggle beam as the latter approaches its lowermost position. A pallet beam I5 extends transversely betwee the sleeves 4 intermediate the upper and. lower base members, 2 and 3., respectively, and is se-.- cured thereto. since the toggle beam 5 and pallet beam. [5 are secured firmly to the sleeves 4, the units, so formed is here. referred to as the stripper assembly.- This assembly reciprocates vertically asthe doubleeacting cylinder 1 is actuated. A. platform Itv projects forwardly and rearwardly from the center of said beaml -Q0il springs l1, rest at the lower ends of said platform. and support at their upper ends a pallet table [8. Bolts extend axially through said springs, and slidably through holes provided. in the. platform and table. to. secure said springs in place. justmentl screws l-9. rest at their lower ends upon said platform, and support at their upper ends a pallet table 20. Adjustment screws l9 are provided upon the platform i6 for vertical adjustment, and are provided with lock nuts for securing said screws in any position desired. The adjustment screws are arranged to contact the pallet table I8 to prevent excessive rocking of the latter during vibration. The pallet table is proportioned and arranged to support a pallet upon which the concrete blocks are carried from the machine after manufacture. Accordingly, as the stripper assembly reciprocates vertically, the pallet 20 reciprocates vertically.

A concrete block mold 22 is held suspended above the pallet table I8 by the free ends of pairs of elongated spring members 23. Said spring members preferably comprise a plurality of leaves 24, 25, 26, and 21. The spring leaves 24 and 25 are joined together by bolts 28 passing through tubular eyes 28 welded to the sides of the frame Similar bolts 29 pass through tubular eyes 30 welded to the sides of said frame, and join spring leaves 26 and 21. Thus at each side of the frame are spring elements, each comprising plural leaves which carry the mold 22. Said spring elements are elongated flat strips of spring material, and are held in substantial parallelism by means of said bolts and said tubular eyes. Said spring elements and the leaves thereof constitute cantilever members, supported at one end and with their free ends joined together by a screw element 3| which passes through the ends of each of said leaves. Said leaves are spaced apart by spacers 32 encircling said screw element and lying intermediate certain of the leaves of the spring elements. That is to say, said spacers lie between the leaves 24 and 25, and between the leaves 25 and 26. Spacing the leaves 26 and 2'! apart is a pad eye 33, joined by capscrews 34 to the side of the concrete block mold 22 at each side of the latter. The screw element 3! at each side of the concrete block mold 22 is joined by a connecting rod 35. The upper end of said connecting rod is bifuracted as at 35c, straddlin an eye 3la at the lower end of screw element 3|, and being joined thereto by a pin 36. The lower end of each of said connecting rods is flattened and has an eye 35b formed thereon. In the bore of said eye is an eccentric cam 31 fixed to drive shaft 38. Thus said drive shaft rotates the eccentric cam, and the connecting rod is reclprocated back and forth. The movement of its upper bifurcated end 35a transmits motion to the screw element 3| and therewith to the concrete block mold which is joined thereto by the pad eye 33. The eccentric movement of the lower end of the connecting rod is not transmitted to said concrete block mold, due to the fact that the pin 36 journals ,in the bifurcated end 35 and thus movement of the mold box is limited to the' path defined by the free end of the spring ele- 'ments 23. Because said spring elements are relatively long and are secured at one end and are free at the end at which they carry the concrete block mold, said mold is limited to more or less pure vertical movement as is indicated by the double headed arrows in Fig. 3 of the drawings. This is oneof the important features of our invention.

Said shaft 38 is driven by a pulley 39 joined to the drive pulley 40 of the motor 4| by belt 42.

The material of which said concrete blocks are made in our machine is deposited from hopper 43 by feeding means which are not particularly pertinent to an understanding of our present invention, and which are described in detail in the application for patent heretofore identified. We preferably provide a substantially dry mixture, and this flows into the concrete block mold and is supported by the pallet 20 which underlies and seals the bottom thereof. That is to say, said concrete block mold comprises ends and sides, is open at the top and bottom, and the pallet 23 seals said bottom. When concrete blocks are being formed within said mold, the pressure head 44 enters through the top of the mold and compresses the contents thereof between the head of said pressure head and said pallet. Pressure isapplied to the material of which said concrete blocks are made while said mold is being subjected to vibration produced by the rotation of the drive shaft 38 acting through the connecting rods 35 to flex the elongated spring members as has been commented upon.

Thereafterthe pallet 20 is lowered by the stripper assembly and the blocks have been compressed and vibrated so that they are firm and will not crumble and collapse. The retraction of the pallet is in a vertical plane, and thus is parallel to the vibrational path effected by the movement of the connecting rods. The pallet is relatively slowly moved downwardly, and the vibrational rate is quite high. Thus, while said blocks are being ejected on the pallet the sides and ends of the concrete block mold move rapidly over them to trowel them and to give them a smooth surface. The truly linear vertical vibration of the concrete block mold tends to produce excellent compaction of the material making up said concrete blocks while said blocks are within the mold and are subject to vibration and pressure. The relatively slow withdrawal of the pallets and therewith the concrete blocks supported thereby, while said vertical vibration continues, tends to smooth and trowel the sides of said concrete blocks without subjecting them to any disruptive forces.

We claim:

1. In a machine for making concrete blocks, the combination of a frame, spring elements joined to said frame and subject to ilexure only along a path which is substantially vertical, a box-like mold having sides and ends but no bottom partially supported by said spring elements, vibrator means for shaking said mold rapidly, means for limiting the movement of said mold to the path defined by the fiexure of said spring elements, and ejecting means for said mold, which ejecting means is operable to discharge formed blocks through the open bottom of said mold along a path substantially parallel with that defined by the flexure of said spring elements, sa'id ejecting and vibrator means being operable at one and. the same time so the block is vibrated during ejection, said spring elements each comprising a plurality of leaves, spaced apart and joined at spaced points along their length tocause them to flex together and in parallelism.

2. In combination with a casting machine having a frame, a, plurality of elongated parallel leaf springs, each said spring having a first end secured to said frame and a second end free to flex with respect thereto, said springs being secured in substantially horizontal planes to limit the flex of said second ends to a substantially verticaldirection, an open bottomed mold box. partially supported by said second ends, vibrator means for vibrating said mold in a sub-, stantially vertical direction as constrained by said second ends, said vibrator means including a pair of connecting rods joined to said mold to limit the movement thereof to said substantially vertical direction, and ejecting means operable while said mold box is being vibrated to eject formed blocks through the open bottom of said mold box.

3. In combination with a casting machine having a frame, a, plurality of parallel leaf springs each having a first end secured to the frame and a second end free to flex with respect thereto, an open bottomed mold box partially supported upon said second ends, for movement therewith, a movable pallet underlying said mold box and defining a removable bottom therefore, vibrator means for vibrating the mold box in a direction guided by the flex of said leaf springs, and ejecting means joined to said pallet to lower the same and eject a formed block through the REFERENCES CITED The following references are of record in the 10 file of this patent:

UNITED STATES PATENTS Number Name Date 1,921,003 Romie Aug. 8, 1933 2,235,440 Mackert Mar. 18, 1941 2,298,446 7 White Oct. 13, 1942 2,397,695 Schutt Apr. 2, 1946 2,541,734 Akers Feb. 13, 1951

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