US 2256361 A
Description (OCR text may contain errors)
Sept. 16, 1941.
BLOCK MAKING APPARATUS AND METHOD OF MANUFACTURE Filed April 9, 1958 III F. J. STRAUB 2,256,361
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BLOCK MAKING APPARATUS AND METHOD OF CTURE MANUFA Francis J. Straub, New Kensin'gton, Pa. Application April 9, 1938, Serial No. 201,122
My invention relates to the art of making concrete building blocks, and. particularly to the method and means for imparting-surface treatment thereto while the aggregate is still plastic.
In the manufacture of such blocks. made of asuitable aggregate such. as sand and gravel, cinders, etc., mixed with cement and water and subjected to tamplng operations, it is desirable in some cases to secure a smooth or approximately smooth outer surface. In my prior Patents Nos. 1,651,420, 1,682,359, 1,692,355, 1,987,721, 2,099,946 and 2,111,701 are disclosed means and the method of so treating one or more sides of a block.
Such treatment to that extent has proven generallysatisfactory insofar as horizontal or vertical reciprocably applied, or curvingly applied. Trowelling or smoothing is-involved, with a degree of accompanying densiflcation and local surface segregation of-the finerparticles of the mix.
In each of such prior disclosures the several various effects are the result of oscillating action shape and dimensions, I utilize a more or less conventional open bottom housing or mold box having side walls 2 and end walls 3 mounted-in any convenient manner, as on a foundation 4.
A hopper 5, of conventional form, is mounted as at 0, for sliding movement over to and away from registering position with the open top of the sure application, as by pressure plate or tampby one or more mold forming walls against the static surfaces of the block.
While as stated, satisfactory results as to surface smoothing and densiflcation are secured,
the various constructions and means'utilized involve more or less additional mechanism and expense in addition to the standard mold box and its parts per se.
The present invention has in view static maintenance of the mold box or any of its walls or inner .faces, with reciprocation of the cona tuated through gears II from any suitable power I tained block-in-process, for trowelling action.
The invention consists of the following described means for effecting such treatment and the novel method of manufacturing blocks there'- by, as embodied in the 'hereinafterdescribed machine illustrated in the accompanying drawing, in which:
Fig. 1 is a vertical section of the machine showing the stationary mold and its parts completely filled with aggregate in-co'mpressed lowered position;
Fig. 2 is a similar view showing the aggregate at the limit ofits upward movement, with the tampers elevated.
Fig. 3 is a similar view on the line III-III of Fig. 1 showing the hopper removed after com- Fig. 4 is a view like Fig. of the finished block;
3 illustrating election Fig. 5 is a perspective view of a block as made.- For the formation of a block of any desired 56 ing operations, such upward impulses are alternately opposed to downward impulses. In either case the sides and ends of the block-ln-formation are caused to be subjected. to trowelling or smoothing action against corresponding faces of the mold box.
In the construction shown I support the usual pallet -l on a reciprocable supporting base plate 8 for vertical reciprocation within the walls 2 and 3 of the mold box. For such action suitable means are provided, as cams 9 on shafts l0, ac-" source, as a motor l2. 1
Such actuating mechanism is controlled by suitable switch or controlling means adapted to arrest operation of'the cams at their lowermost position, as in Fig.1. The aggregate is supplied as required by bringing the sliding hopper 5 into open register with the mold box, and for usual functioning of the tampers l3, at variable depths.
In operation, compression of aggregate as supplied proceeds upwardly above the pallet 1 until completion of the block, in the usual manner. Alternating movement of the mass of aggregate in process of densiflcation is effected by the raising of the supporting pallet and its base against the opposing lowering forces of gravitation or vibration and tamping or compression, as the pallet recedes, until the block is completedof fulldepth.
Cam action then being arrested with the cams lowered, accompanied by elevated inaction of the upper compressing members, any surplus is then removed by the hopper. Thereafter the completed block is ejected by the usual lifting posts or bars H as in Fig. 4, the finished block and its pallet are removed for storage and drying, and the operation is repeated.
It will thus beseen that, due to the altemating reciprocation of the block-in-formation throughout all stages, with more or less supplemental vertical action and compression after complete filling, the finished block will be con-' sistently and uniformly trowelled, condensed,
and smoothed over the side and end faces. Moreor less definite minute parallel lines or grooves d and e are usually formed on these faces, in the same general manner as is disclosed in my prior Patent No. 2,099,946.
proved appearance and accompanying advantages.
It will be understood that the invention may be utilized in or by the construction shown, or as modified in various details as to operative elements, dimensions, or otherwise to adapt it to different conditions of use, within the scope of the following claims.
1. Block making apparatus consisting of an open top stationary mold box, means providing an alternating upwardly actuated and downwardly non-resistant movable bottom therefor, and means for ,compressing aggregate against the movable bottom during its positively actuated elevation and non-resisted lowering.
2. Block making apparatus consisting of an open top stationary mold box, a movable bottom, means effecting uniformly continuous positive gradual limited upward movement and providing for alternating equal uniformly continuous unopposed gradual downward movement of the bottom, and means providing for compression of aggregate in opposition to the bottom and said means at all positions of such continuous limited movements.
3. Block making apparatus consisting of an open top stationary mold box, a movable bottom, elevating and lowering means effecting positive limited upward and gravitating lowering move- 4 'ment of the bottom and contained aggregate, means for successively supplementing already compressed aggregate with additions thereto, and means providing for compression and,limited movement of the ag regate in successive zones by action in opposition to its upward movement and during its equally limited downward movement whereby to effect continuous compression and reverse smoothing against the inner faces of the stationary mold box.
4. In a block making apparatus, the combination of an open top stationary mold box having a vertically reciprocable pallet-supporting plate, means for intermittently elevating said plate for a fraction only of its entire discharge travel and for permitting lowering of the plate and contents under pressure, and aggregate compressing means in the form of individual tampers opposing said means at varying planes upwardly during formation of the block whereby to impart to the contained aggregate alternating smoothing movement against the inner faces of the mold boxduring its progressive formation,
and independent means for upwardly discharging the plate and finished block thereon with final trowelling of its sides and ends against the inner mold faces.
5. In a" block making apparatus, the combination of an open top stationary mold box having a vertically reciprocable pallet-supporting plate, cam mechanism controlling movement of said plate and a pallet thereon at a uniform rate upwardly and downwardly for a fraction only of its entire discharge travel against tamping compression, and aggregate compressing means opposing said means at successively varying planes upwardly during formation of the block whereby to impart to the aggregate alternating limited smoothing movement against the inner faces of the mold box during its progressive formation, and independent means for discharging the plate and finished block thereon with final trowelling of its sides and ends against the inner mold faces.
6. The method of making a concrete building block consisting in charging portions of plastic aggregate within a stationary mold box and with upward accumulation therein above a bottom support, subjecting the accumulating mass to continuous intermittent impact pressure from above at successively ascending zones, and simultaneously to opposing limited upward and alternating lowering movement whereby the entire mass during condensation is caused to be moved upwardly and downwardly within the stationary mold box with final upward ejection therefrom and resulting smoothing action against its confining wall faces.
" FRANCIS J. STRAUB.