IL38322A - A method and a machine for the manufacture of elongated concrete building blocks - Google Patents
A method and a machine for the manufacture of elongated concrete building blocksInfo
- Publication number
- IL38322A IL38322A IL38322A IL3832271A IL38322A IL 38322 A IL38322 A IL 38322A IL 38322 A IL38322 A IL 38322A IL 3832271 A IL3832271 A IL 3832271A IL 38322 A IL38322 A IL 38322A
- Authority
- IL
- Israel
- Prior art keywords
- forming
- machine
- concrete
- band
- mould
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B28—WORKING CEMENT, CLAY, OR STONE
- B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
- B28B1/00—Producing shaped prefabricated articles from the material
- B28B1/08—Producing shaped prefabricated articles from the material by vibrating or jolting
- B28B1/084—Producing shaped prefabricated articles from the material by vibrating or jolting the vibrating moulds or cores being moved horizontally for making strands of moulded articles
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Ceramic Engineering (AREA)
- Mechanical Engineering (AREA)
- On-Site Construction Work That Accompanies The Preparation And Application Of Concrete (AREA)
- Devices For Post-Treatments, Processing, Supply, Discharge, And Other Processes (AREA)
- Press-Shaping Or Shaping Using Conveyers (AREA)
- Manufacturing Of Tubular Articles Or Embedded Moulded Articles (AREA)
- Nitrogen- Or Sulfur-Containing Heterocyclic Ring Compounds With Rings Of Six Or More Members (AREA)
Description
38322/2
A method and a machine for the manufacture
of elongated concrete building blocks
Tieao j'aa o»a*«o o'p 1?:. -nj-'V mraav a»»w
tively thin and edgewise arranged concrete building blocks t¾r using the slide mould technique according to which a concrete mixture is eirrg- discharged from a continuously advancing container down onto a bed, vibrated directly beneath said container, and formed into a layer the longitudinal sides of which being parallel relativelytoeach other and the upper surface of which smoothened. Because the two vibrating side walls of the mould during the continuous advancement thereof on the bed slide in a direction towards the concrete object thus formed, there is a risk that cracks may form as a result of the fri6tion between the forming wall and the concrete object. For this reason, the advancing speed of the slide mould must be limited. As a rule, the speed cannot exceed 1.5-2 meters per minute.
BRIEF SUMMARY OF THE INVENTION
The purpose of the present invention is primarily to attempt to increase the moulding speed proper apd yet obtain a concrete element of predetermined dimensions exhibiting no cracks. In accordance with the invention this is made possible in that the concrete layer is being moulded between a vert-i-cai-ly-poe-iti-oired- feeder band and a forming wall, said feeder band being rolled out in synchrony5with the speed of advancement of the container and the forming wall being positioned at a distance laterally relatively said band and moving together with the container and being arranged to vibrate laterally in a manner known -per _se while compacting the concrete mixture fed into the space between said band and said wall from the container. Owing to the combination of a feeder band, rolled out as indicated, and a vibrating forming wall arranged at a distance from said band and extending in the advancing
.direction of the mould, it becomes possible to increase the moulding speed to 6 meters per minute or more. The manufac- turing costs naturally are reduced accordingly. Because there is no relative displacement between the feeder band and the moulded concrete element there is no risk of crack formation in the element.
When forming elements between two vibrating forming walls running in parallel in accordance with earlier known methods an extremely accurate adjustment of the forming walls as well as careful metering of the concrete mixture from the container is required. By using a feeder band in combination with a vibrating forming wall in the mould it becomes possible to allow the gap between these two mould parts to taper in the direction towards the rear mould end and to apply a load to the rear end of the resilient wall while using a resilient means
shi ft
such that said wall may swing- to the side to permit a momentary increase of the mould width at the mould outlet end when an excess of concrete mass is being discharged from the container. In such cases the concrete element is given a slightly increased thickness in the corresponding area but this does not, however, constitute a drawback. Nor is there in this area any risk that cracks may occur, which of course is. of importance.
The invention also concerns a machine for performing the novel method, said machine comprising a' frame which is movable over an .elongate bed in the longitudinal direction thereof and which is provided with one or several containers intended to hold the concrete mixture, said container or containers having concrete mixture outlet openings at their lower portion, and forming side walls for moulding the side faces of the concrete
invention is the provision of a VCTti lly^osd--ien-ed- feeder band constituting one of the forming sides and adapted to bo rolled out at the same speed as the frame is being advanced on the bed, and of a vertically positioned wall constituting the opposite forming side and having means to vibrate it laterally.
In accordance with a preferred embodiment of the invention the feeder band is provided with recesses spaced equal distances apart. These recesses form corresponding projections on the external face of the moulded concrete element. When the latter is in the form of a supporting beam and two such supporting beams are placed adjacent one another and joined together by means of, for instance, mortar, these projections ensure a strong bond between the beams and prevent the latter from being displaced relatively each other in the horizontal or the vertical directions.
BRIE? lEggRIPTIOW OF THE DRAWINGS '
Further characteristics of the invention and the advan-. tages obtained thereby will become apparent upon reading the following detailed description, in which:
Figs. 1-3 illustrate schematically a machine in accordance with the invention,
Fig. 1 being a side view showing in partial longitudi-nal section a machine for the manufacture of a channel-shaped beam of concrete,
Fig. 2 being a cross-sectional view through the machine along line II-II in Fig. 1 with certain parts broken away for the sake of clarity, and
Fig. 3 being a plan view of the left side of the machine opposite one feeder band thereof.
Pig. 4 illustrates in a side view a more detailed arrangement of the machine.
Pig 5. illustrates on an enlarged scale a plan view of the machine in accordance with Pig. 4.
Pig 6. is also a plan view of the machine in accordance with Pig. 5t "the concrete mixture containers having, however, been omitted therefrom.
Pig. 7 is a cross sectional view through th machine and illustrates on an even larger scale a cross-section through the machine along line VII-VII of Pig. 6.
Pig. 8 is a cross-sectional view along line VIII-VIII of Pig. 6.
Pig. 9 shows on an even larger, scale a modified embodiment of the device for supporting the right vibrating forming wall in accordance with Pig. 8. <
Pig. 10 is a perspective view of one end of a concrete element formed by the machine in accordance.with the previous
Figures. ^
rei nforci ng
Pig. 11 is a perspective view of -frrmett-Ping irons included in the concrete elements, and
Pig 12 is a vertical section through two mutually interconnected concrete elements.
DETAILED DESCRIPTION OP A PREFERRED EMBODIMENT
Pig. 10 illustrates a furrow-like or channel-shaped concrete element 1 having two vertical walls 2,3 and a bottom
4 extending between said walls. The concrete element 1 is reinforced by means of U-shaped, longitudinally extending -ar- rei nforci ng rei nforci ng
mmrring- irons 5 and transversally extending smouEiag- irons 6 having upright end portions or legs 7. Additionally, a longi- rei nforci ng Λ „
tudinal -atrmourittg- iron 8 is arranged inside each wall 2,3.
Each channel wall 2, 3 is provided on its external face wit.
projections 9 spaced an equal distance apart. Concrete elemen-^ of this kind are intended to he manufactured by means of the machine in accordance with the invention while using the slide- moulding technique.
The frame 10 of the moulding machine illustrated in
Pigs. 4-9 is supported on running wheels 11, 12 running along the longitudinal edges 13 of an elongatedbed 14. The wheels 12 are driven by a motor 15 via chains 16 or other motion-trans- itting means. The frame 10 supports three moulds 17,18, and 1 for moulding the channel walls 2,3 and bottom 4, respectively, of the concrete element 1. The bottom of each mould 17, 18, and 19 is formed by bed 1 .
The outer wall of the moulds 17 8 is formed by a ver- tically positioned feeder band 20, 21 made from rubber or some other 'suitable resilient material/Each band runs over two vertical rollers 22, 23 the latter of which is driven by the motor 15 at such a speed and in such a direction as to permit the bands 20, 21 to be rolled out at the rate of advancement of the machine along the bed. This means that the side of each band 20, 21 facing its associated mould 17, 18 does not move relatively to the moulded object. A supporting wall 24 positioned in contact with the reverse side of the band 20, 21 takes up the pressure from the mould. The bands 20, 21 are provided with outwardly
• ' spaced projecting, vertical ribs,, or similar projections 25 spfreed- an equal distance apart along the lower edge of the bands.
' The bands form the outer forming or moulding walls of the
■ moulds 17, 18. The opposite forming wall of each mould 17 and
18 comprise an elongatedplate 27 and 28, respectively, these . plates being provided with vibrator means 26 and supported
: through resilient means 29, 30 and 31, 32, respectively,
arranged at the forward and the rear ends, respectively, on φ horizontal shafts 33, which are rigidly connected to longitu- dinally extending "beams 34 on . the frame 10. Special means are 5 provided to displace walls 27, 28 to positions closer to or '' ■'·.;'..'; further away from each hand 20, 21 to lesse or increase,
: ; according to wish, the width of the moulds and consequently
the thickness of the channel walls 2, 3.
As illustrated in Pig. 9 it is also possible to adjust 10 ' the walls 27, 28 in such a way that each mould 17, 18 will taper in the direction towards the trailing end 35, i.e. such that the . walls 27,.28 converge towards the bands 20, 21 in the rearward
direction - the advancing direction of the moulding machine being indicated by arrow 36 in Fig. 1. In accordance with Pig. 9 the 5 shaft 33' is provided with external screw threads meshing with
internal screw threads in a nut sleeve 37, which sleeve is
rotatably, but axially not displacably mounted in its associated ' . beam 34.
At its top portion, each mould 17, 18 terminates in a 0'·.'. slide 39 connected to a vibrator means 38. The moulds 17, 18
also comprise longitudinally extending shaping ribs 40 and 41
positioned immediately above the bed 14.
The mould 19 intended for moulding the bottom 4 of the . channel also terminates at its top portion in a slide 43 which 5 ' is associated with a vibrator means 42 and has. resilient and
longitudinally extending sealing ribs 44 which are loosely united with the forming walls 27, 28.
■ ; Ahead of the moulds 17, 18, and .19, as seen in the
direction of advancement of the moulding machine, the frame 10 0 /,, supports two containers 45, 46 holding a concrete mixture, each
.. such container comprising a metering device 47 and 48, ,
respectively, arranged at the outlet opening 49 and 50, ^
respectively. Below the outlet opening 49 a funnel 51 or
similar means is arranged to spread concrete mixture in an
. even layer 52 in the middle of the "bed 14. Ahead of the funnel
51 a nozzle 53 is arranged, said nozzle "being connected to a
• - water supply for spraying water onto the slope- 4 being formed
at the forward edge of the concrete layer 52.
Below the outlet or discharge opening 50 a distributor
funnel 55 is mounted to divide the concrete being discharged .
.. . from the container 46 in such a way that an equal amount of
concrete flows down into each mould 17 and 18. Immediately
■ below each outlet opening 6 of the distributor funnel 55 is
positioned the. rear end of a guide pipe 57 for the longitudinal
rei nforci ng
armoTirlTTg iron 8. The pipe 57 is connected to a source of water
rei nforci ng
■ supply such that the a-rme¾a?±ng- iron 8 when leaving the rear end of
sl oped part
■■:;·■ the guide pipe 57, is wet and, in addition the slxrpe 58 being
formed at the forward end of the 'concrete layer 59 formed at
sl i ghtl
■... the end walls 2 and 3, respectively, is soiaewhat wetted.
The machine operates in the following manner. Initially, rei nforci ng ' '
the armo¾a?ii¾g- irons 5, 6, and 7 which have been previously put
' 1 in order and partly shown in Pig. 11 are placed centrally on
'the bed 14 in the longitudinal direction -of said bed such that
rei nforci ng i rons
the uprights 7 of the armours extend into the moulds 17 and 18 . ,-, ' of the machine. When the latter is put into motion and driven r at a predetermined speed in the direction indicated by arrow 36 ; ·? in Pig. 1 , a concrete mixture is - eing dispensed out of the con-i tainer .45 down onto the centre field of bed 14 in a layer 52 of
sufficient thickness. The layer is being- compacted by the vib- rator means 42 and smoothened by the slide 43. At the same time,
' - 8 - ' .' . ' 'v
■ ' concrete is being discharged from container 46 down between ^ the iron uprights 7 in the moulds 17, 18, where the concrete
mixture is being compacted primarily through the vibrating of the walls 27, 28 and to some extend also through the vibrating of the slides 39, which latter means simultaneously smoothen the upper
edge of the concrete element 1 just moulded. The slides 39 are
• so adjusted that the walls 2 and 3 are given the intended correct height. Also the forming walls 27, 28 are adjusted at the correct distance away from their associated band 20, 21. It is then
possible to allow the forming walls 27, 28 and the bands 20, 21
to converge towards the outlet end (rear end) of the moulds 17, 18 by approximately 20°, which facilitates the feeding of the concrete
densely
and also makes possible to compact it heav-i-ly in the moulds 17, 18. If, for some reason, a momentary excess of concrete mixture -1-5- discharged from the container 46 into the moulds, the walls
27, 28 bulge to a corresponding degree at their rear end 3 away from its associated band 20, 21. The result then is that the .
walls 2, 3 will become somewhat thicker in this area, which
. 'obviously has no detrimental effect on the concrete element
itself. The transverse dimensions of the concrete element 1 as
a whole, i.e. the distance between the external faces of the
walls 2, 3, are determined by the bands 20, 21 by means of their ' 'supporting walls 24 which are non-resilidnt in an outwards
direction. This arrangement ensures that the finished concrete ,: elements all are given the same width and the channel walls 2
and 3 also the same height.
' To make possible that the concrete mixture streams
continuously and in an even flow down onto the bed 14 a relatively dry concrete mixture is used. The water cement ratio should as a rule be as low. as about 0,27 - 0,35.
As a consequence of this comparatively low water/cement *
ratio a product of great strength and tenacity is obtained.
Another advantage inherent with this concrete mixture is that
sticking between the side surfaces of the formed product and
the sides of the mould is eliminated. However, in order to
ensure that during compacting the dry concrete mixture is
; ' made to completely enclose t erea^nnri¾g- irons" 5, 6, a small
amount of water is added through nozzle 53 to the concrete
reinforcing
; ' layer 52, and to ensure that ,the longitudinal arnrottring irons 8 0 · . are likewise well embedded in the concrete a small amount of water is added through pipe. 7 such that the concrete mixture around
; the iron 8 becomes more fluid and easy-flowing.
Pig. 12 illustrates the way in which two concrete
elements 1 manufactured in accordance with the invention and
.·. resting on a transverse beam 60 are interconnected with mortar
inserted in the gap 61 between the adjacent longitudinal walls
2, 3 of the elements. Because the mortar penetrates between the
projections 9 on the elements a firm bond is obtained, rendering
1 impossible mutual displacement of the concrete elements relatively 0 to each other in the' - vertical as well as in the longitudinal
. direction.
The embodiment as shown and illustrated is to be regarded as an example only and the various parts 'of the moulding machine ·■ ':·. may be varied constructively in a variety of ways within the
scope of the appended claims. For .instance, the invention is not
limited to moulding channel-chaped concrete elements but also
■'■/,··'■ other, relatively narrow beams, such as T-beams, positioned on
■ j. ·.'·' ..' ■
.·'■ ■" their small edge, are with the same advantage and with the same
manufacturing capacity manufactured by means of a machine in
0. accordance with the present invention.
. - Ί0 - ' ' '""
Claims (9)
1 . A method of manufacturing through sl ide-moulding concrete building elements of elongated configuration and preferably comparatively thin and arranged edgewise, said si 1 de-moulding being performed by discharging a concrete mixture from a continuously advancing container down onto a bed, and vibrating said concrete directly beneath said container to form a layer having mutually paral lel longitudinal edges and a smooth upper surface , the method comprising moulding said layer between two surfaces , one of which consisting of a feeder band being rol led out 1n synchronism with the speed of advancement of the container, and the other one consisting of a forming wal l arranged at a distance lateral ly of said band and being displaced together with said container, said forming wal l being caused to vibrate 1n the lateral direction 1n a manner known per se while compacting the concrete mixture being discharged Into the space formed between said band and said forming wal l from said container.
2. The method claimed in claim 1 , comprising effecting compacting of the concrete mixture 1n the space formed between said feeder band and said forming wall , also by decreasing the cross-sectional area of said space 1n the direction towards the mould outlet end.
3. A machine for performing the method defined In the preceding claims , comprising a frame , an elongated bed over which said frame travels 1n the longitudinal direction of the bed, one or several containers for holding concrete mixture, an outlet opening arranged at the lower portion of said container of containers for discharging concrete mixture, forming side wal ls for moulding the side surfaces of the concrete layer being formed on said bed, comprising a feeder band constituting the one forming side of the mould, sai d band being arranged to be rol led out 1n synchronism with the advancement of the frame along the bed , and a vertically positioned wal l constituting thefopposlte mould forming side , said wall being provided with means for vibrating it in the lateral direction.
4. A machine as claimed 1n claim 3, wherein a space , forming the mould, Is delimited between said feeder band and said vibrating forming wall positioned In facing relationship with said band, said space decreasing with regard to its cross-sectional dimensions in the direction towards the outlet (rear) end.
5. A machine as claimed in claim 4, wherein said feeder band and said vibrating forming wal l converge 1n the direction towards the outlet end.
6. A machiae as claimed in claim 3, wherein said vibrating forming wall 1s plvotably mounted about an imaginary vertical axis extending at the forward end of the mould.
7. A machine as claimed in claim 3, wherein said vibrating wall 1s supported in said frame so as to be movable lateral ly for altering the width of the mould and consequently the thickness of. the object moulded 1n said machine.
8. A machine as claimed in claim 3, wherein notches are provided for forming corresponding projections in the external face of the concrete element moulded 1n said machine.
9. A machine as claimed in claim 3, wherein resi lient means are provided for urging the end of the vibrating forming wall, closest to the
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE1695670 | 1970-12-15 |
Publications (2)
Publication Number | Publication Date |
---|---|
IL38322A0 IL38322A0 (en) | 1972-02-29 |
IL38322A true IL38322A (en) | 1974-12-31 |
Family
ID=20303048
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
IL38322A IL38322A (en) | 1970-12-15 | 1971-12-08 | A method and a machine for the manufacture of elongated concrete building blocks |
Country Status (18)
Country | Link |
---|---|
JP (1) | JPS5417766B1 (en) |
AT (1) | AT318458B (en) |
BE (1) | BE775319A (en) |
CA (1) | CA946593A (en) |
CH (1) | CH537263A (en) |
CS (1) | CS159298B2 (en) |
DE (1) | DE2152124B2 (en) |
DK (1) | DK126976B (en) |
ES (2) | ES398004A1 (en) |
FI (1) | FI52676C (en) |
FR (1) | FR2118494A5 (en) |
GB (1) | GB1337298A (en) |
HU (1) | HU171636B (en) |
IL (1) | IL38322A (en) |
IT (1) | IT940056B (en) |
NL (1) | NL158424B (en) |
NO (1) | NO130048B (en) |
ZA (1) | ZA718140B (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2128654A (en) * | 1982-10-12 | 1984-05-02 | Balfour Beatty Ltd | Wall panel |
IT1195098B (en) * | 1986-07-11 | 1988-10-12 | Russo A & C Sas | PLANT FOR THE PRODUCTION ON TRACK OF ALVEOLAR PANELS IN REINFORCED CONCRETE OR PARTIALLY PRE-COMPRESSED OR WITH SLOW REINFORCEMENT EXTENDED TO THE LOWER AND UPPER SURFACES AND TO THE RIBS AND DERIVED PRODUCT |
FR2671119B1 (en) * | 1990-12-28 | 1993-04-09 | Saret France | CONCRETE CONSTRUCTION ELEMENTS, PRE-STRESSED, OF THE PRELABS TYPE, INSTALLATION AND METHOD FOR THEIR MANUFACTURE. |
ES2155293B1 (en) * | 1997-02-04 | 2001-12-16 | Extremadura 2000 De Estructura | MANUFACTURING PROCEDURE OF PRETENSED PLATES TYPE PI BY EXTRUSION. |
-
1971
- 1971-10-18 CA CA125,319A patent/CA946593A/en not_active Expired
- 1971-10-19 AT AT902971A patent/AT318458B/en not_active IP Right Cessation
- 1971-10-19 GB GB4847071A patent/GB1337298A/en not_active Expired
- 1971-10-20 DE DE2152124A patent/DE2152124B2/en active Granted
- 1971-10-27 IT IT70522/71A patent/IT940056B/en active
- 1971-10-29 DK DK529171AA patent/DK126976B/en unknown
- 1971-10-30 CH CH1574271A patent/CH537263A/en not_active IP Right Cessation
- 1971-11-03 FI FI713135A patent/FI52676C/en active
- 1971-11-12 BE BE775319A patent/BE775319A/en unknown
- 1971-11-14 NL NL7115634.A patent/NL158424B/en unknown
- 1971-11-17 JP JP9157371A patent/JPS5417766B1/ja active Pending
- 1971-12-01 FR FR7143960A patent/FR2118494A5/fr not_active Expired
- 1971-12-06 ZA ZA718140A patent/ZA718140B/en unknown
- 1971-12-08 IL IL38322A patent/IL38322A/en unknown
- 1971-12-10 HU HU71NI00000143A patent/HU171636B/en unknown
- 1971-12-14 NO NO04610/71*[A patent/NO130048B/no unknown
- 1971-12-14 CS CS869071A patent/CS159298B2/cs unknown
- 1971-12-15 ES ES398004A patent/ES398004A1/en not_active Expired
- 1971-12-15 ES ES398005A patent/ES398005A1/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
CH537263A (en) | 1973-05-31 |
GB1337298A (en) | 1973-11-14 |
ES398005A1 (en) | 1974-07-01 |
DK126976B (en) | 1973-09-10 |
AU3490371A (en) | 1973-05-03 |
ES398004A1 (en) | 1974-07-01 |
FI52676C (en) | 1977-12-01 |
NL158424B (en) | 1978-11-15 |
IL38322A0 (en) | 1972-02-29 |
SU438162A3 (en) | 1974-07-30 |
IT940056B (en) | 1973-02-10 |
CS159298B2 (en) | 1974-12-27 |
FI52676B (en) | 1977-08-01 |
ZA718140B (en) | 1972-08-30 |
CA946593A (en) | 1974-05-07 |
BE775319A (en) | 1972-03-01 |
DE2152124B2 (en) | 1974-02-14 |
DE2152124A1 (en) | 1972-07-20 |
JPS5417766B1 (en) | 1979-07-03 |
AT318458B (en) | 1974-10-25 |
NL7115634A (en) | 1972-06-19 |
DE2152124C3 (en) | 1974-09-19 |
FR2118494A5 (en) | 1972-07-28 |
HU171636B (en) | 1978-02-28 |
NO130048B (en) | 1974-07-01 |
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