U.S. patent number 3,758,934 [Application Number 05/229,057] was granted by the patent office on 1973-09-18 for method of and apparatus for separating lightweight (aerated) concrete elements.
This patent grant is currently assigned to Intong Aktiebolag. Invention is credited to Borje Hasselgren, Wilhelm Sebardt.
United States Patent |
3,758,934 |
Hasselgren , et al. |
September 18, 1973 |
METHOD OF AND APPARATUS FOR SEPARATING LIGHTWEIGHT (AERATED)
CONCRETE ELEMENTS
Abstract
Apparatus for separating a stack of adhering lightweight
concrete elements comprises upper and lower pairs of mutually
opposite elongate clamping units, the units of each pair being
mounted for generally horizontal relative clamping movement toward
each other so that the two pairs can grip adjacent elements in the
stack. At least one clamping unit, preferably in the upper pair, is
mounted for movement normal to the clamping direction so as to
pivot the upper element relative to the adjacent lower element and
separate these elements. This unit, and preferably all the units,
comprises a multitude of single clamping jaws arranged for
individual and independent movement in the clamping direction so as
to compensate for possible irregularities in the elements of the
stack. The clamping jaws are carried by pivotally mounted arms, the
arm being pivotally mounted on a vertically movable carrier so that
the clamping jaws can be moved downwardly to effect separation of
all elements in the stack. This avoids the necessity of removing an
upper separated element before the next lower element can be
separated. A method of separating the elements comprises the
described operation of this preferred apparatus embodiment.
Inventors: |
Hasselgren; Borje (Taby,
SW), Sebardt; Wilhelm (Bromma, SW) |
Assignee: |
Intong Aktiebolag
(Hallabrottet, SW)
|
Family
ID: |
20259813 |
Appl.
No.: |
05/229,057 |
Filed: |
February 24, 1972 |
Foreign Application Priority Data
|
|
|
|
|
Feb 24, 1971 [SW] |
|
|
2352/71 |
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Current U.S.
Class: |
29/426.2; 29/239;
29/426.5; 414/796.6; 414/796.9 |
Current CPC
Class: |
B28B
13/04 (20130101); B28B 11/145 (20130101); B65G
59/02 (20130101); Y10T 29/53683 (20150115); Y10T
29/49822 (20150115); Y10T 29/49817 (20150115) |
Current International
Class: |
B28B
11/14 (20060101); B28B 13/00 (20060101); B28B
13/04 (20060101); B65G 59/02 (20060101); B28b
013/04 (); B23p 019/00 (); B23p 019/02 () |
Field of
Search: |
;29/2D,427,2R,426
;214/8.5R,152 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Eager; Thomas H.
Claims
We claim:
1. A method of separating lightweight concrete elements mutually
delimited by essentially horizontal cuts but adhering to each other
to form at least one block of stacked multiple elements, comprising
the steps of causing one upper pair and one lower pair of mutually
opposite elongate clamping units each to grip in a tong-like manner
its respective element of two elements situated on either side of a
cut, and imparting to at least one clamping unit of one pair a
movement relative to the other pair, thus separating one element
from the other, wherein at least one clamping unit in each pair
consists of a multitude of single clamping jaws which are moved
individually and independently of each other toward the opposite
clamping unit to grip the respective elements, thejaws of at least
one of the jaw-type units being moved simultaneously across the
clamping direction during the separating operation to effect said
separation of one element from the other.
2. A method according to claim 1 wherein each stacked element after
being separated is left remaining in the block until essentially
all elements lying on top of each other have been separated.
3. A method according to claim 2 wherein the block, after
separation of all its stacked elements, is lifted by lifting the
lowermost element so as to lay bare its bottom, and at least one
pallet is inserted under the block, which is then lowered and
brought to rest on said pallet.
4. A method according to claim 2 wherein the block comprises at
least one first stack and one second stack horizontally adjacent
each other and containing elements of different dimensions, and
wherein in a first step the topmost element of the first stack is
separated and in a second step the topmost element of the second
stack is separated, after which the clamping units are controlled
alternately to hold and separate elements of the different piles,
the clamping units continuously moving downwardly until all
elements have been separated from each other.
5. A method according to claim 1 wherein the jaw-type unit which is
moved across the clamping direction is one unit of the upper pair,
and moves relatively to the other unit of the upper pair and both
units of the lower pair so as to effect a pivotal movement of the
element being separated.
6. Apparatus for separating lightweight concrete elements delimited
by essentially horizontal cuts but adhering to each other to form
at least one block of plural stacked elements, said apparatus
comprising one upper pair and one lower pair of mutually opposite
elongate clamping units, means mounting the units of each pair for
relative clamping movement toward each other to have each pair grip
in a tong-like manner a respective element of two elements situated
on either side of a cut, at least one clamping unit of at least one
pair being mounted for movement also across the clamping direction
to bring about a pivotal movement of one element relative to the
other for separating said elements from each other, at least one of
the units in the upper as well as in the lower pair of clamping
units comprising a multitude of single clamping jaws arranged for
moving individually and independently of each other toward the
opposite clamping unit during the clamping movement, the clamping
jaws of at least one of said jaw-type clamping units being movable
together and simultaneously across the clamping direction for
effecting said separating of the elements.
7. Apparatus according to claim 6 wherein both units of each pair
consist of a multitude of single clamping jaws, and said
across-movable unit comprises one of the units of the upper pair
which moves across the clamping direction relative to the other
unit of the upper pair and relative to both units of the lower
pair.
8. Apparatus according to claim 7 wherein each of said clamping
jaws is mounted on a pivotally mounted arm, the arms for the
across-movable upper clamping jaws being mounted on pivots free of
adjacent pivots on which are mounted the arms for the adjacent
lower clamping jaws.
9. Apparatus according to claim 8 wherein the arms of all the
clamping jaws which are movable across the clamping direction are
connected mutually by a common synchronizing shaft for effecting
the simultaneous movement of the clamping jaws across the clamping
direction.
10. Apparatus according to claim 9 wherein the arms of the
across-movable clamping jaws are connected to the synchronizing
shaft via a linkage for effecting the simultaneous movement of the
arms across the clamping direction.
11. A device according to claim 10 wherein the synchronizing shaft
is rotatable and said linkage comprises a bracket fixed to the
synchronizing shaft and connected to said pivots around which said
across-movable arms are mounted so as to move said pivots in said
across direction.
12. Apparatus according to claim 11 wherein the synchronizing shaft
is turned by means of at least one hydraulic motor.
13. Apparatus according to claim 8 wherein the mutually opposite
upper clamping jaw arms and the mutually opposite lower clamping
jaw arms are connected at their upper ends above said pivots by
piston-and-cylinder devices for effecting said clamping
movements.
14. Apparatus according to claim 13 wherein each of the arms
consists of at least two mutually connected adjacent struts, the
arm of each upper clamping jaw being mounted between the struts
which together form the arm of a lower clamping jaw.
15. Apparatus according to claim 13 wherein the clamping jaws and
their pivotal arms are carried by an elongate carrier of
essentially U-shaped cross section, and means mounting the carrier
for vertical movement.
16. Apparatus according to claim 15 wherein the distance between
the lower clamping jaws and the horizontal part of the U-shaped
carrier which unites the depending shanks of the U-shape is at
least almost as long as the maximum height of a block of stacked
elements to be separated, such that the lower clamping jaws can
grip the lowermost element of a stack when said carrier is moved
downwardly.
Description
FIELD OF THE INVENTION
This invention relates to a method of and apparatus for separating
lightweight concrete elements.
BACKGROUND AND SUMMARY OF THE INVENTION
Lightweight concrete products may be produced in the following way:
Down into a casting mould a lightweight concrete-forming mass is
poured which, having been made porous by means of gas generating or
foaming agents for instance, is brought to bind or harden into a
semiplastic more or less cheese-like consistency. The casting mould
mentioned frequently consists of a parallelepipedon-shaped box open
upwards which advantageously may have the length 600 cm, the width
120 cm and the height 60 cm. This means that the mass cast will
have its plane or its large surface oriented horizontally. When the
mass, as has been said, has bound into a block of semiplastic
self-bearing consistency, this block is raised on its edge, i.e. is
turned by 90.degree. so as to get its large surface oriented
vertically, and, after that, it is subjected to a dividing
procedure, preferably by bringing wires, operating horizontally as
well as vertically, to pass through the block, thus cutting it up.
This dividing of the block may proceed in almost an unlimited
number of ways. The raised block may e.g. be divided by horizontal
cuts only into four elements measuring 600 .times. 60 .times. 30 cm
or six elements measuring 600 .times. 60 .times. 20 cm and so on.
But it is possible, too, by the so-called dimension change, to
divide the block into elements of quite different dimensions and
ranges of application. The dimension change may be carried out by
making one or more slots in the block, into which slots cutting
frames of varying wire distribution are then brought in. Elements
of many dimensions are of course possible to produce e.g. by
arranging two or more slots for the dimension change. Finally the
divided block is brought into an autoclave to be cured by means of
steam and to obtain its final strength.
After the curing is finished, the cuts dividing the block into
single elements, may most closely be characterized as crack
indications. This is due to a phenomenon which is here called
adhesion and implies that the elements stick to each other strongly
enough to prevent them from being separated without anything
further. The adhesion is particularly manifest in the downmost cuts
of the block where, as is natural, the weight of the block itself
provides an extra pressing-together of the elements. Within the
lightweight concrete technique there have appeared many methods and
devices for the separating of lightweight concrete elements
sticking together in the said way.
Thus, through the Swedish Patent No. 164 138 a device is known
which comprises one upper and one lower pair of mutually opposite
longish clamping units arranged to hold or to grip like tongs each
its own of two lightweight concrete elements situated on either
side of a dividing slot, one clamping unit of the upper pair being
movable vertically or across the clamping direction to provide a
swinging of one element relatively to the other so as to separate
the elements from each other. More strictly spoken both units of
the upper pair together form an upper frame box and those of the
lower pair, likewise, a lower frame box, whereby one clamping unit
of each pair has the shape of a rigid pressure plate covering all
the length of the block and movable to and from the opposite unit,
by means of hydraulic cylinders for instance. The frame boxes are
hinged mutually, affording the possibility of swinging the upper
one relatively the lower one by means of special vertically acting
pressure boxes. This device worked satisfactorily inasmuch as the
separating, as a consequence of the swinging movement, proceeded
easily and smoothly. Those investigations, however, which have lead
to the present invention, sometimes revealed crack formation and
other non-desirable damages in elements separated by means of the
device in question. The reason for that has proved to be the fact
that unevennesses, be they ever so small, in the sides of the
elements cause the relatively great forces emanating from the
straight and longish pressure plates to act unevenly along the
sides of the elements, pressure strain thus occurring locally.
Another disadvantage of the device is that it involves the
necessity of removing each element from the block immediately after
the separation, by means of a lifting stirrup for instance, and
bringing it onto a piling pallet or other place of storing. This
means complicated and extremely slow separating operations. The
present invention refers to a method which lacks the disadvantages
described above and, besides, has several advantages as compared to
earlier known methods within the field. Characteristic of the
method invented is that the elements are held by pairs of clamping
units of which at least one in each pair consists of a multitude of
single clamping jaws which when clamping, are brought to move
individually or independently of each other towards the opposite
clamping unit of the pair, the jaws of at least one unit during the
separating operation being brought to move together or
simultaneously across the clamping direction.
Additionally, the invention also refers to a separating device for
practicing the method. Characteristic of this device is that at
least one of the units in the upper as well as in the lower pair of
clamping units consists of a multitude of single clamping jaws
arranged for moving individually or independently of each other
towards the opposite clamping unit during the clamping procedure,
and in that the clamping jaws of at least one clamping unit are
movable together or simultaneously across the clamping direction
for bringing-about said separating of the elements. Other
distinctive features and advantages are seen from the attached
claims. The expression lightweight concrete elements in this
connection firstly refers to elements of aerated concrete or foam
concrete, i.e. kinds of concrete obtained by using gas producing or
foaming agents respectively, but it is of course also possible to
adapt the invention to every other kind of lightweight concrete
afflicted with problems of sticking.
With reference to the attached drawings a detailed description is
given below of a preferred embodiment of the invention as an
example. In the drawings FIG. 1 is a longitudinal partly sectional
assembly view of the device on a first scale, FIG. 2 a somewhat
enlarged cross section II -- II of FIG. 1, FIG. 3 a still more
enlarged cross section of the most vital part of the device, FIG.
4, 5 and 6 show partly sectional vertical views IV -- IV, V -- V,
and VI -- VI respectively of FIG. 3 and FIG. 7 an extremely
enlarged detail of the device. FIG. 8 provides a strongly schematic
plan view of a plant including the separating device.
In the Figures, 1 is the general designation of a lightweight
concrete block resting on a support 2 which may be carried by
wheels for instance. In this case the block is shown divided up
into two different parts or piles 3 and 4 by a dimension change
slot 5, the first pile 3 in its turn having been divided into six
longish elements 6 by means of horizontal cuts 7 having the nature
of indications, whereas the other pile 4 has been divided into
several elements 8 by horizontal as well as vertical cuts marked 9
and 10 respectively.
The invented device comprises a stationary stand with the general
designation 11, composed of a number of vertical columns 12,
longitudinal beams 13 and cross beams 14. The beams together form a
frame structure resting on the columns. In the frame structure 13 -
14 there is a carrier 15 suspended which in its turn carries one
pair of upper clamping units 16 and 17 and one pair of lower ones
18 and 19. See FIGS. 2 and 3. In accordance with the invention
these clamping units consist of a great number of single clamping
jaws, in FIG. 1 marked with a - z.
To explain more clearly how the clamping jaws cooperate with the
carrier 15 special reference is made here to FIGS. 3 - 6. From
these Figures it is seen that all the clamping jaws of units 16 -
19 are situated each on the lower end of one of the equally
numerous arms 20, 21, 22 or 23 respectively, which are essentially
vertical. Thus the upper clamping jaws 16 and 17 belong together to
those arms which are here called upper arms 20 and 21, while the
lower clamping jaws 18 and 19 belong together to the arms 22 and 23
here called lower arms. These arms all are possible to swing or
move around shafts or shaft pivots oriented horizontally or
parallelly to the longitudinal direction of the carrier. Turning of
the arms is carried out in this case by means of telescopic bars 24
and 25 the former of which via hinges 26 mutually connects the
upper arms 20 and 21 while the latter one via hinges 27 connects
the upper ends of the lower arms 22 and 23 to each other. The
telescopic bars may suitably consist of hydraulic cylinders
encompassing reciprocating pistons. The bars thus can be lengthened
when the clamping jaws by turning of the arms are to be caused to
move towards each other in order to grip a lightweight concrete
element. Loosening of the clamping jaws is brought about by
reducing the length of the bars.
The carrier 15 is composed of a great number of sheets 28 placed
crosswise and being of a U-shaped profile. These are mutually
connected by longish beams or plates 29 (FIG. 3), the structure
thus becoming rigid lengthwise as well as crosswise. Inside the
carrier there is arranged a U-plate 30.
From FIG. 4 is seen that the arms 21 and 23 shown in FIG. 3 to the
right of the lightweight concrete block 1, encompass a pivot 31
common to them both. Such a pivot 31 is kept in position by holders
32 situated at the lower parts of the sheets 28. From FIG. 4 it is
seen, too, that the lower arm 23 consists of two parts or struts 35
and 36, and that upper arm 21 consists of struts 33 and 34. The
arms are mounted on the pivot by bearings 37 and 38. It is evident
from the above that the pivots 31 are rigidly connected to the
carrier 15 and that the sole possibility of moving the arms 21 and
23 is to swing them.
It is otherwise with the arms 20 and 22 shown in FIG. 5. Truly
enough the lower arms 22 are mounted with bearings on unmovable
pivots 39 fixed to holders 40 situated at the lower parts of the
sheets 28, but of the upper arms each one is mounted with a bearing
around pivot 41 movable relatively to the carrier 15. The pivot 41
is by a bracket 42 connected to a synchronizing shaft 43 stretching
uninterruptedly along all the length of the carrier. The
synchronizing shaft is possible to turn but the brackets 42 for all
pivots 41 have been fixed to the shaft 43 in question, by welding
for instance. The shaft -- as is perhaps best seen from FIG. 6 --
is mounted in hubs 44 fixed to the lower parts of the sheets 28.
The possibility of turning the shaft in this case is provided by
hydraulic cylinders 45 fixed to the carrier 15. The number of these
cylinders may suitably coincide with that of the brackets to get an
evenly distributed loading though it would in itself be thinkable
to use only one or few hydraulic aggregates for turning the shaft.
The piston 45 of the hydraulic aggregate or the rod 46 of the
piston is via a hinge 47 connected to an upright 48 which, like the
bracket, is fixed to the shaft 43 though in this case the
connection is perpendicular to the bracket. It will be evident
that, when the pistons of the hydraulic aggregates are moving
inwards in the cylinders, the shaft 43 will turn anti-clockwise at
least by some little distance, while the brackets 42 are swinging,
causing the pivots 41 with their pertaining arms 20 and clamping
jaws 16 to move upwards. At that procedure all the upper clamping
jaws 16 move upwards simultaneously according to the invention.
FIG. 3 shows now there are rubber wedges 49 on the clamping jaws 16
- 19 to make contact with the lightweight concrete elements.
Now again reference is made to FIG. 1. Here is illustrated that the
carrier 15 is movable vertically by means of two synchronized
hydraulic cylinders 50 and 51. The vertical movement of the carrier
is controlled by a shaft 52 situated at the top of the carrier and
provided both with wheels 53 running in vertical guides 54 on the
hanging beams 55 and with cog wheels 56 meshing with straight cog
bars 57 on the hanging beams. On the carrier there are housings 58
for driving aggregates supplying power to the different parts of
the device.
As will most clearly be evident from FIGS. 2 and 3 the distance
between the lower clamping jaws 18 and 19 and the horizontal part
of the carrier which unites both its downward shanklike parts is at
least almost as long as the height of the block or pile 3. In this
case the distance between said horizontal part of the carrier and
the lower clamping jaws is a little longer than the height of the
block.
The device described operates in the following way: A lightweight
concrete block 1, already cured, is brought in, resting on the
support 2, to a position under the carrier 15 and the vertical
position of the latter is adjusted so as to place the upper pair of
clamping jaws 16 and 17 above the cut at hand between the topmost
element 6a or 8a and the next one, 6b or 8b, and to place the lower
pair 18 - 19 under the cut of the pile in question, i.e. 3 or 4,
respectively. See FIG. 2. In this position the telescopic bars 24
and 25 are elongated causing the clamping jaws of each pair to bear
against the sides of the elements and to grip these. It should be
noticed here that in a first stage, for example, only the clamping
jaws a - h work those adjacent pile 3 (i-z) being kept apart. When
the synchronizing shaft 43 is turned by the hydraulic aggregates 45
far enough to bring the clamping jaws 16 to move about 10 mm
vertically. This causes the element or course of elements 8a to
revolve relatively to elements 8b, the elements thus being
separated. In the next stage (FIG. 2) the clamping jaws i - z
adjacent pile 3 are brought to work, those adjacent pile 4(a-h)
being kept apart. The carrier 15 is lowered far enough to bring the
pairs of clamping jaws on both sides at the level of the upmost cut
of the pile 3. The clamping jaws i - z are caused to grip the
upmost element 6a which revolves and is separated by turning the
synchronizing shaft. In a third stage the carrier is brought to
sink further down in order to bring the clamping jaws a - h into
their working positions on each side of the next-to-topmost cut in
the pile 4, after which the operations described are repeated
alternately until all elements or courses of elements in both piles
3 and 4 have been separated. FIG. 3 illustrates an exemplary
subsequent stage. Finally both piles are lifted somewhat from the
support 2 to make it possible to insert pallets or similar bearing
devices under them, and the piles are brought down to rest on these
pallets, ready to be transported to some suitable place of storing
or unloading.
It is evident from the above that all single elements after being
spearated from the block in question remain resting each on the
other until all the elements at hand in the pile have been
separated. There is, thus, no question of removing the elements one
after another from the pile as they are being spearated, such as
has been the case for earlier known methods and devices within the
field. The possibility of keeping all elements in the pile brings
about essential advantages as the total time consumption for the
separating and the arranging of the elements into piles possible to
store, is reduced to a minimum, handling damages, particularly in
the edges of the elements are also manifestly reduced and to this
there is a saving of tools.
In FIG. 8 an example is given of how the described separating
device may be arranged in a plant for the separating and storing of
lightweight concrete elements. In the Figure the totality of the
separating device is marked with 60. 61 signifies one or more, in
this case two, tracks or transport lines leading from an
autoclaving or curing station to a traverser pit 62. In this pit
there is arranged a traverser truck 64 movable to and fro laterally
along rails 63 or similar. On the traverser truck 64 there are
rails or transport lines 65 for the support 2 which is movable
longitudinally and carries the piles 3 and 4 of the lightweight
concrete elements 6 and 8 respectively. From the separating device
60 there leads a transport line 66 for transporting the support 2
in and out. For support most often plane sheets, so-called curing
plates, are used. At the side of the traverser pit 62 one or more
tracks 67 are arranged for the accumulating of piles. FRom the
traverser pit there are one or more tracks 68 leading to one or
more stores, e.g. a store 69 for reinforced elements 6 and a store
70 for unreinforced elements 8. 71 signifies a store of pallets 72
of suitable sizes. The plant described may of course be modified in
many ways. Thus the separating device 60 may be movable instead of
stationary, an economy of transport lines being gained. Further the
cured elements may be taken into the separating device via the
tracks 66 instead of the tracks 61, the latter thus made away
with.
The plant normally functions in the following way: The elements are
taken into the separating device 60 either directly via the tracks
66 or via the tracks 61 and the traverser truck 64. They are
separated in the manner described above being brought to rest on
pallets 72. From the separating device the elements are brought to
the stores 69 and 70 via the traverser truck 64 and the tracks or
transport lines 68.
HOwever, it is many times advantageous to accumulate many piles 3
or 4 containing elements of the same dimensions to get a support
carrying exclusively the same sort of elements before starting the
separting operation. For that purpose the ranging tracks 67 are
used on which supports can be kept standing until they have been
filled for instance with unreinforced elements 8 of uniform
dimensions. If the plant is run in that way, the alternate
operations mentioned previously of the clamping jaws of the
carrier, are no more necessary. It is of course also possible to
separate all elements of one pile before separating those of the
second one. But then the carrier 15 will have to be brought up and
down two times instead of one.
The hydraulic aggregates belonging to the device here described may
suitably be connected to a special operating panel from which the
operations are controlled in an optional way not shown here,
preferably electronically.
The advantages of the invented method and device are evident as the
clamping forces are evenly distributed along all the length of the
element because of the multitude of the clamping jaws. The number
of these jaws may suitably be 3 - 6, preferably 4, per meter.
Another advantage is that the device allows for the separating of
blocks of different dimensions. This is particularly important for
elements of different thickness and different profiles, e.g.
tongue-and-groove elements contra plain elements.
It is self-evident that the invention is not limited to that
embodiment only which has been described and shown in the drawings.
Thus it is possible to use carriers movable also horizontally by
being suspended to an overhead travelling crane or by wheels at
hand on the stand 11. Instead of hydraulic operating, naturally,
other ways of running the plant may come into question, such as
pneumatic, mechanic or similar running. Many other modifications,
too, are possible within the scope of the following patent
claims:
* * * * *