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1. * GB785318 (A)
Description: GB785318 (A) ? 1957-10-23
Improvements in or relating to borated dextrine
Description of GB785318 (A)
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PATENT SPECIFICATION
785,318 Date of Application and filing Complete Specification Jan 26,
1955.
No 2408/55.
Application made in United States of America on Feb 16, 1954.
Complete Specification Published Oct 23, 1957.
Index at Acceptance: -Class 121, A.
International Classification: -CO 9 i.
COMPLETE SPECIFICATION
Improvements in or relating to Borated Dextrine We, NATIONAL STARCH
PRODUCTS INC, a corporation organized under the laws of the State of
Delaware, one of the United States of America, of 270 Madison Avenue,
City of New York, State of New York, United States of America, do
hereby declare the invention, for which we pray that a patent may be
granted to us, and the method by which it is to be performed, to be
particularly described in and by the following statement: -
This invention relates to the production of improved borated dextrines
More particularly, it relates to dextrine-borax adhesives which may be
dispersed in cold water without agglomeration into lumps.
It is well known that starch may be converted by heat, with or without
added catalysts, to produce the class of starch conversion products
known as dextrines, including that type of dextrine ordinarily known

2. as British Gum.
Depending upon the type and amount of added or natural catalyst
present, as well as the time and degree of heating, the resulting
conversion products may vary in solubility from those which are
essentially insoluble in water to those which are 100 % soluble
Similar types of conversion products may sometimes be achieved by
treatment of starch with suitable enzymes.
Our invention pertains to those dextrines (including British Gums)
which are at least % soluble in cold water (water at room
temperature).
Dextrines are extensively used in a large number of industrial
adhesive applications.
For this purpose, the dextrine must of course be dispersed or
dissolved in water, the dispersion or solution being applied to paper
or other surfaces as an adhesive in such operations as convolute or
spiral tube winding, case and carton sealing and tight-wrapping paper
wrappers on cartons.
In order to achieve the desired qualities of adhesiveness, viscosity
and tackiness, it is customary for many applications to use for the
above purposes a borated dextrine, that it, a mixture of dextrine and
borax The borax content may vary, depending upon the particular use,
from about 72 % to about 25 %, based on the weight ra of the dextrine
While lesser amounts of borax are sometimes added to dextrines, for
various reasons, such mixtures are not suitable for many important
industrial adhesive applications.
In many modern, large-scale industrial operations requiring the use of
adhesives, relatively large quantities of adhesive must be prepared at
one time Thus in some large operations quantities in the order of 2000
pounds of dextrine are dissolved in water to supply one day's need of
adhesive Obviously, any difficulty or delay in preparing the dextrine
solution represents a serious point of inefficiency in the particular
manufacturing operation involved.
In this connection, it should be noted that when speaking of "
dissolving " dextrine in water to form a " solution ", one refers to
dispersing the dextrine so as to produce a homogeneous material that
may range from a clear, transparent fluid to an opaque paste,
depending upon the particular dextrine and the amount of water The
more highly converted the dextrine, the greater will be the proportion
forming a true solution, the remainder being in the form of a hydrated
colloidal dispersion.
When referring to a solution of dextrine, therefore, we include in
that term any homogeneous dispersion of dextrine in water, regardless
of what proportion, if any, may be truly dissolved in the purely
scientific sense.

3. Borated dextrines, of the types heretofore known, have been
characterized by a tendency to lump formation when mixed in water In
other words, when mixing the dry dextrine with water, instead of a
smooth, homogeneous dispersion being formed, portions of the dextrine
agglomerate into lumps or balls.
When examined closely, these lumps appear to consist of an exterior
surface composed of wetted, pasty dextrine, enclosing an interior
portion which is dry and unwetted by the water Mere agitation is not
sufficient to break up these agglomerates, and in practice the mixture
of dextrine and water has to be allowed to stand for as much as
twenty-four hours, and even then the lumps do not always disperse.
Obviously, this represents a serious bottle-neck in the manufacturing
operation of which the adhesive application is a part.
Many attempts have been made to solve this problem of lump formation
in dextrine solutions, with varying degrees of success, but none
heretofore has resulted in a commercially feasible method for
producing borated dextrines which would dissolve in water readily and
without perceptible lump formation.
We have now discovered a method for producing substantially
non-lumping dextrines.
According to our invention, dextrine is treated in the following
manner: a) The dextrine is moistened, preferably by spraying water
upon it, with vigorous agitation, until the dextrine has a moisture
content of from about 9 %O to about 18 %, based upon the weight of the
anflydrous dextrine.
b) The thus moistened dextrine is blended with at least about 7-% of
borax based upon the anhydrous weight of the dextrine Quantities of
borax as high as 25 % or more may be used, depending upon the
particular properties desired in the final product Borax itself is of
course sodium tetraborate decahydrate However, the borax called for by
our process may include sodium metaborate, so long as the total
quantity of borax-metaborate, expressed as borax, is present in the
proportion of at least 7-%, based on the anhydrous dextrine It is
understood, therefore, that xvihen we refer to the presence of borax
in the mixture of our invention we include in that term borax itself
or mixtures of borax and sodium metaborate The sodium metaborate may
be added as a separate ingredient, or it may be formed in situ by
adding an appropriate alkali (e g.
sodium hydroxide or sodium carbonate) to the dextrine-borax mix.
c) In addition to the borax, there is added a normally solid
hydroscopic or deliquescent chemical This latter material may be any
chemical capable of absorbing or adsorbing substantial proportions of
water, even to the point of going into solution upon exposure to air
of normal humidity Representative examples of such water-sorptive

4. agents are potassium acetate, ammonium acetate, ammonium thiocyanate,
calcium chloride, urea, zinc chloride, magnesium chloride, aluminum
nitrate, aluminum chloride, ferric nitrate, copper nitrate, magnesium
calcium chloride, magnesium nitrate, potassium carbonate, potassium
cyanate, potassium thiocyanate and calcium nitrate In this connection,
it should be pointed out that the water-sorbing agent may be organic
as well as inorganic The water-sorbing chemical may be present in the
proportion of from about 22 % to at least %, based upon the weight of
the borax.
While larger proportions are not harmful, they appear to be
unnecessary Ordinarily, it is preferred that the chemical be in finely
powdered form It is sometimes found desirable to employ combinations
of two or more of such chemicals.
The required amount of moisture may be added to the dextrine at the
time of or immediately subsequent to its manufacture, or 70 the
moisture may be added to a dry dextrine at the time that the other
above-mentioned ingredients are added.
In our preferred practice, water is sprayed into the dextrine, using
any convenient blend 75 ing apparatus, until the dextrine contains
from about 9 to 18 %,' moisture As indicated, above, this step may be
unnecessary, if the dextrine already contains therequired amount of
moisture There are then added the borax (or 80 borax-metaborate, or
borax-alkali) and one or more hydroscopic agents, in the proportions
noted The mixture is blended thoroughly to assure uniform admixture.
It has been found that as a result of the 85 combination of these
three elements (moisture, borax and hygroscopic agent) the resulting
dextrine is substantially changed in appearance, and remarkably
improved in its solution characteristics Whereas ordinary dextrine, as
com 90 mercially available, is a soft, silky, extremely fine powder
which tends even in the dry state to agglomerate and cake somewhat
like dry starch, the product of our invention is changed in physical
form so as to resemble fine grains 95 of sand, discrete and
non-agglomerating The product of our invention is found to be darker
in colour than the corresponding untreated dextrine This, tegether
with the change in physical form, suggests that a chemical and/or 100
physical reaction has taken place within the blend It is believed that
through some interaction of the dextrine with the moisture, the borax,
and the hydroscopic material, the original fine particles have been
fused into dry, 105 hard, sand-like grains, with some chemical action
being indicated by the color change.
When the sand-like dextrine of our invention is mixed with water,
there is an amazing absence of any tendency toward lump forma 110 tion
Each grain appears to absorb water and disperse as an individual
entity, as contrasted to the tendency of ordinary dextrines to

5. agglomerate into balls or lumps with dry, unwetted cores 115 As a
result, the dextrine of our invention may be thoroughly dispersed to
produce a working adhesive, in a matter of minutes The exact time will
depend to some extent upon the volume of adhesive being prepared at a
given 120 time For large, commercial batches, a period of from 2 hour
to about 4 hours is sufficient to produce a homogeneous, lump-free
dispersion.
This should be contrasted vith thle previously known dextrines, which
required many times 125 this period for proper dispersion, meaning in
practice that the dextrine had to be mixed with water one day for the
next day's consumption.
Depending entirely upon availability, economics and the final use to
which the 130 785,318 785,318 adhesive is to be put, the dextrine may
be one made from miaze, potato, tapioca, sago or any other starch The
remarkable improvements stemming from the combination of ingredients
called for by our invention are apparent regardless of the source of
the dextrine.
We prefer to employ a dextrine which is % to 100 % soluble in water in
the ratio 1 dextrine: 100 water at 720 F, the solubility being
determined as follows: 2 grams of the dextrine are dispersed smoothly
in 200 cc water at 720 F, using a flask which is then stoppered
tightly and agitated in a constant temperature bath at 72 F for 2
hours The material is then centrifuged for 5 minutes, or until clear.
cc of the clear solution are removed by pipette into a weight
evaporating dish, and evaporated in an oven for 4 hours, at 2200 F.
After cooling in a desiccator, the weight of the residue is determined
The percent solubility of the dextrine is then calculated from the wt
of residuex 1000 equation % solubility2 In this connection it should
be pointed out that mixtures of dextrines of varying solubilities may
be employed, so long as the average solubility as above determined is
within the limits 60-100 %.
Besides varying in solubility it is known that dextrines also vary in
the viscosites of their aqueous dispersions For the purposes of our
invention we prefer to employ dextrines which come within the
following viscosity range:
when 100 grams of the anhydrous dextrine are dispersed in water with
15 grams of borax, and heated on a boiling water bath for five
minutes, between 150 and 600 grams of water will be required in the
dispersion to result in a viscosity of 84 centipoises at 720 F Here
too, it is possible to use mixtures of two or more dextrines of
varying viscosities, which, in admixture, will fall within the
above-described range.
The following examples will further illustrate the embodiment of our
invention:EXAMPLE I

6. In this and in the subsequent examples, all parts given are by weight
The solubility and viscosity figures for the dextrines used in the
various examples will be indicated in the table immediately following
Example VIIL 100 parts of maize dextrine were sprayed with water, in a
blending vessel, until the dextrine contained 16 % moisture
Maintaining constant agitation, there were then added 10 parts of
borax, 5 parts sodium metaborate and 5 parts of ammonium acetate
Agitation was continued for approximately 2 hour The resulting
composition consisted of free-flowing sand-like particles.
When 1 part of the above-treated dextrine was mixed with 3 parts of
water at room temperature, a smooth, homogeneous dispersion, free of
any perceptible lumps, was formed withini a half hour By contrast,
when 1 part of the above dextrine-borax-metaborate mixture, without
the added ammonium acetate, was mixed with 1 5 parts of water at room
temperature, the material immediately formed lumps containing unwetted
cores of dextrine, and even after standing overnight lumps were still
present.
EXAMPLE II parts of sago dextrine, containing 9 % water, were blended
thoroughly with 15 parts of borax and 5 parts of potassium acetate, at
1850 F.
When mixed with water at 720 F, in the ratio dextrine: 1 water, a
smooth, lump-free dispersion was obtained in less than an hour.
As indicated previously, when large quantities of dextrine were
dissolved, somewhat more time was naturally required, but in no case
did the formation of a homogeneous dispersion require more than four
hours (as contrasted to the 12-24 hour periods required with standard
borated dextrines).
EXAMPLE III parts of sago dextrine were sprayed with water to achieve
a moisture content of 18 %.
There were then added 20 parts of borax, 0 5 parts sodium carbonate
and 0 5 parts of ammonium acetate After thorough blending the dextrine
darkened somewhat in color and assumed the discrete sand-like granular
form previously described.
A smooth, lump-free dispersion was obtained when one part of the above
mixture was mixed with 2 5 Darts of water at 72 F.
for 2 hour.
EXAMPLE IV parts of tapioca dextrine were sprayed 100 with water until
the dextrine attained a moisture content of 14 % There were then
blended in 7 5 parts borax and 7 5 parts potassium acetate.
The resulting granular dextrine was mixed 105 with water at 720 F, in
the ratio of 1 part dextrine: 2 parts water, and a smooth, lumpfree
dispersion was achieved in less than an hour.
EXAMPLE V 110 parts of potato dextrine, containing 15 % moisture, were
blended with 14 parts borax, 2 parts magnesium chloride and 5 parts

7. aluminum nitrate When the resulting sandlike dextrine was mixed with
water at 720 F 115 in the ratio of 1 dextrine: 2 5 water, a smooth,
lump-free dispersion was obtained in less than an hour.
EXAMPLE VI parts of potato dextrine containing 18 % 120 moisture were
mixed with 7 parts borax and 71 parts ammonium acetate After thorough
blending, it was found that the mixture dispersed in 1 5 parts of
water at room temperature with remarkable freedom from lump 125
formation.
785,318 EXAMPLE VII parts of tapioca dextrine were sprayed with water
until the dextrine had a moisture content of 17 % 15 parts of borax
and 5 parts of ammonium thiocyanate were then blended thoroughly with
the dextrine The resulting sand-like mixture dispersed readily in 5
parts of water at room temperature, with notable absence of lump
formation.
EXAMPLE VIII parts of maize dextrine were sprayed with water until a
moisture content of 18 % was achieved There were then thoroughly
blended with the dextrine 16 parts borax, 5 parts sodium carbonate and
5 parts ammonium acetate.
When mixed with water at room temperature a smooth dispersion was
quickly formed with substantially less lump formation, as compared to
a similar blend minus the ammonium acetate, and particularly so as
compared to a blend where the ammonium acetate was not present and the
moisture content of the dextrine was substantially less than 9 %.
TABLE OF SOLUBILITIES AND VISCOSITIES.
In the above examples the dextrines used were characterized by the
following solubilities and viscosities, measured by the herein
described procedures:Example
Solubility Viscosity (Grams H O to give viscosity of 84 cps) I 100 %
150 II 100 % 185 E 100 % 220 IV 100 % 350 V 100 % 240 VI 100 % 240 VII
80 % 570 VIII 60 % 450 When the moisture content or solubility of the
dextrine is in the lower part of the specified ranges, or the
proportion of hygroscopic agent is relatively low, it is sometimes
found advisable to allow the dextrine-borax-hygroscopic agent blend to
age or mature for several weeks before dispersing in water As an
alternative, one may apply heat up to about 1850 F at the time of
blending of dextrine, borax and hygroscopic agent Either of these
steps aids in effecting the reaction among the components of the
blend, and thus results in maximum improvement in the final product.
Summarizing, our invention comprises the unique combination of three
critical substances-high moisture dextrines, borax and a hygroscopic
agent, in the required relative proportions, to produce a dextrine
that is outstandingly superior in its freedom from lump formation when
in the dry state or mixed in water at room temperatures.

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* GB785319 (A)
Description: GB785319 (A) ? 1957-10-23
Improvements in and relating to centrifugal casting
Description of GB785319 (A)
PATENT SPEC WICA Ti ON
Inventor:-REGINALD THOMAS DAVY.
Date of filing Con Mplete Specification: Nov 8, 1955
Application Date: Jan 27, 1955 No 2496155.
Complete Specification Published: Oct 23, 1957.
Index at Acceptance:-Class 83 ( 1), F 16 A 122, F 10 B( 201: 202: 5),
International Classification:-B 22 d.
COMPLETE SPECIFICATION.
Improvements in and relating to Centrifugal Casting.
We, SHEEPBRIDGE STOKES LIMITED, of Chesterfield, Derbyshire, a British
Company, do hereby declare the invention, for which we pray that a
patent may be granted l to us, and the method by which it is to be
performed, to be particularly described in and by ile following
statement:-
This invention relates to the centrifugal casting of pipes or other
cylindrical or like -10 hollow bodies (hereinafter called pipes) and
has reference to a method for forming the interior configuration and
producing a local variation(s) in the bore of said pipes.
Hitherto it has been customary to alter the bore locally (such as to
provide an internal flange) of a centrifugally cast pipe by machining
or by introducing a flanged liner moulded by normal sand-casting
methods.
These methods are open to objections and " O have disadvantages, and

9. the present inveni tion has for its aim the alteration of the bore or
internal configuration of a pipe at one and the same time as the pipe
is formed by the centrifugal casting operation.
According to the invention a preformed annulus or collar of the
desired axial extent having a circular or other shaped inner periphery
is supported within the rotary centrifugal mould in a plane transverse
to the axis of the mould on a temporary closure member comprising a
flanged sleeve extending axially of the mould, through which sleeve
the casting metal may be poured, the said annulus having a maximum
diameter suitably less than the internal diameter of the mould and/or
having transit slots or openings whereby the casting metal can flow
from one side of the annulus to the other in order longitudinally to
complete the casting of the pipe at both sides of said annulus, while
causing the peripheral margin thereof to be embedded in the cast
metal, said lPrice 3 s 6 d l annulus thus constituting an internal
flange in the pipe.
A further feature of the invention consists in shaping the peripheral
surface or edge margin of the annulus with a view to affording
additional resistance to shear or axial stresses likely to be imposed
on the annulus when embodied as a flange or like member in the cast
pipe.
It will be appreciated that after casting, the said annulus
constitutes an internal flange or other member having a different
internal boie or orifice from that of the cast pipe, and is in effect
integral therewith The axial thickness or extent of the flange or
internal member will depend on the purpose for which such is intended
to serve when in the cast pipe.
In the accompanying drawings:Fig 1 is a fragmentary longitudinal
section of a centrifugal mould illustrating a preformed internal
member according to the invention, and mode of supporting it in
position on an orificed closure member for one end of the mould; Fig 2
is a similar view to Fig 1 showing the metal being poured into the
mould; Fig 3 is a similar view to Figs 1 and 2 showing the final stage
of casting when the internal member is embedded in the centrifugally
cast pipe; Fig 4, A, B, C and D, are fragmentary sections illustrating
several peripheral forms for the internal member; Fig 5 is a
fragmentary section illustrating another peripheral form for the
internal member; and Fig 6 is a corresponding fragmentary end
elevation of the member seen in Fig 5.
In carrying the invention into effect according to one mode as
described by way of example, a centrifugal casting apparatus 785,319
such as described in Patent Specifications
Nos 581,777 and 594,412 is employed and one or both ends of the rotary
mould 1 is fitted with an end plate or closure member 2 either or both

10. of which has a tubular extension or sleeve 3 through the central
orifice of which a casting metal pouring, spout 4 (Fig 2) is
introduced such that the mould may be charged from one or both ends.
The closure member 2 may have its flanged part fitted into a recess or
rebate la of the mould and temporarily held in position by a wedge pin
lb or other means.
Describing one of the closure members adapted for the purpose of the
invention, the sleeve 3 projects axially inward into the zone to be
occupied by the flange to be incorporated in the cast pipe This sleeve
towards its inner end has a circular rebate 3 a in the said zone The
circular face of the rebate parallel to the axis of the mould has a
diameter such that an annulus 5, which is to constitute the flange,
may snugly fit when positioned against the shoulder or transverse face
of the rebate Any other suitable means may be provided for supporting
and locating the flange-forming annulus 5 in position on the sleeve
extension 3 a If two flanges are to be provided within the pipe to be
moulded, for example if a flange is to be located towards each end of
the pipe, a second closure plate (not shown) of the above character is
similarly mounted at the opposite end of the mould with the sleeve
directed inwardly for positioning said second annulus The second
closure plate may have an orificed sleeve if pouring is intended to
take place from both ends of the mould, otherwise the sleeve may be
closed on either its inward or outward end.
The interior diameter of the sleeve or sleeves is suitable for the
reception of the nozzle through which the molten metal may be poured
into the mould, as seen in Fig 2.
'I he external diameter of the annulus 5 for either or both ends of
the mould is preferably substantially less than the internal diameter
of the mould and such that the annulus will be embedded in the
centrifugally cast metal but preferably not to such an extent that the
annulus will penetrate through the cast pipe 6 (see Fig 3) to the
outer surface thereof.
The interior surface of the mould may be sprayed or coated according
to known practice with refractory material or it may be coated or
sprayed with a graphitic die dressing, which may be in powder form.
With the end closures in position and one ( 60 or both of such being
fitted with the preformed annulus 5, metal 7 is poured into the mould
1 from one or both ends through the spout 4 which protrudes through
the pouring orifice of the sleeve 3 of the closure(s).
This is accomplished while the mould is being rotated When the rate of
rotation of the mould reaches the centrifugal casting speed the metal
will flow over the internal surface and spread longitudinally The
peripheral margin of the annulus will be 70 immersed in the casting
metal and there will be fusion between the surface of the annulus and

11. the casting metal such that the annulus becomes an integral flange
member in the cast pipe 8 (see Fig 3) On completion of 75 the casting
the closure member 2 is withdrawn from the mould and the pipe
extracted.
The exterior periphery or edge of the annulus may be a plain
cylindrical surface (see Figs 1, 2 and 3) parallel 'with the axis 80
of the mould or it may be given a configuration or form which is
calculated to enable the flange to resist or to have its resistance
increased to torque stresses and/or stresses imposed axially Several
alternative forms 85 of periphery for the annulus are seen in Fig 4,
A, B C and D, and in Figs 5 and 6.
In order to increase the resistance to axial thrusts the annulus may
be circumferentially corrugated or ribbed, as at 5 a (Fig 4 A), or 90
it may be formed with a peripheral concavity or groove, as at 5 b (Fig
4 B) Where the thrust is unidirectional or greater in one direction
than another, the periphery of the annulus may be bevelled, as at 5 d
(Fig 4 D), 95 in a direction to offer increased resistance, or where
the thrust may be imposed from either direction axially, the annular
periphery may be convexly curved, as at Sc (Fig 4 C), or provided with
oppositely disposed bevelled sur 100 faces Alternatively, or in
addition, the periphery may be stepped or shouldered For increasing
resistance to torque the periphery of the annulus may have a series of
radial slots e, or the peripheral surface may be ribbed or 105
corrugated in a direction parallel to the axis of the mould According
to another form (not shown) adapted to resist torque the side margins
of the annulus to be embedded may have lateral radial ribs or recesses
110 The torque resisting form may be combined with any of the forms of
periphery shown in Fig 4.
In some forms, such as when the annulus is deeply embedded to the
maximum degree 115 in the casting metal, the annulus may be drilled or
slotted from side to side at the edge margin or adjacent the periphery
with holes affording a free passage for the metal, and such holes will
afford a keying hold 120 between the pipe and the flange.
Closure plates with sleeves of different lengths may be provided for
locating the flange (or like) forming annulus or annuli in any
suitable position(s) along the axis of 125 the mould Alternatively,
the closure plates may be provided with interchangeable sleeves of
different lengths which may be removably secured in the pouring
orifice by screw-threaded or other means 130 i i 1 785,319 stresses
which may be imposed on the internal flange formed by the annulus when
embodied in the cast pipe.
4 In centrifugal casting as claimed in
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* GB785320 (A)
Description: GB785320 (A) ? 1957-10-23
Improvements in or relating to means for securing ceiling boards or the like
in place
Description of GB785320 (A)
PATENT SPECIFICATION 7 f
Date of filing Contplete Specification: Feb 8, 1956.
Application Date: Feb 8, 1955 No 3762/55.
Complete Specification Published: Oct 23, 1957.
Index at Acceptance:-Class 20 ( 4), T.
International Classification:-E 041.
COMPLETE SPECIFICATION.
Improvements in or relating to Means for Securing Ceiling Boards or
the like in Place.
I, HAROLD CHURCHMAN, a British Subject, of 77179 Copthall House,
Copthall Avenue, London, E C 2, do hereby declare the invention, for
which I pray that a patent may be granted to me, and the method by
which it is to be performed, to be particularly described in and by
the following statement:-
This invention is for improvements in or relating to means for
securing ceiling boards or the like in place, and has for one of its
objects to provide a more efficient construction than has heretofore
been available The term "ceiling boards or the like" is intended to
include fibre building boards, plaster boards, asbestos sheeting,
plywood and glazing, whether used on ceilings or walls.
The invention is concerned with securing means of the type in which a
runner, carried by roof purlins or the like or otherwise suspended
from a roof or supported by the building structure, comprises a

13. stiffening backbone and provides a ledge upon or against which latter
and marginal portion of the ceiling or like board is held -by a wire
clip In Specification No 661,063 a onepiece runner of girder
cross-section is described comprising a backbone and two continuous
opposed ribs integral therewith which converge towards the backbone
and receive a marginal portion of a ceiling or like board between them
In Specification
No 663,109 a two-part runner of girder cross-section is described
which is similar to that described in Specification No 661,063 but the
backbone which forms one part of the runner has outside the position
of the ceiling or like board an integral channel the mouth of which is
laterally directed and receives the second part of the runner This
second part is a cover strip which will be exposed when the ceiling or
like boards are assembled, and is shaped to engage in the lPr.
aforesaid channel and to reach out laterally beyond the latter to
cover the margin of an assembled ceiling or like board.
According to the invention there is provided securing means, of the
type above described, in which the ceiling or like board is held
against the ledge on the runner by a wire clip which is of cranked
formation at the middle portion of its length so that when it is in
operative position the middle portion of its length reaches right
through the thickness of the backbone of the runner at a position
between the opposed faces of the ceiling or like board when the latter
is resting against the ledge, and the end portions of its length
closely overlie that face of the board which is remote from the ledge.
Preferably, the backbone of the runner is formed with a slot to
receive the cranked clip, which slot is elongated in the direction of
the length of the runner to permit the passage of a crank in the clip
prior to the clip being turned into operative position, in which
position the cranked formation prevents dislodgement of the clip.
Conveniently, at the junction of the main part of the clip and a
cranked portion thereof an extension of the latter is provided which,
when the clip is in operative position, reaches beyond that face of
the ceiling or like board which is closely overlain by the main part
of the clip.
The backbone of the runner may be formed separately from the ledge
portion thereof but may overlap the latter in such manner that the
portion of the securing clip which reaches through the backbone may
also reach through the ledge portion, thus connecting together the two
parts of the runner The two parts of the runner may take various forms
For instance, the ledge portion may be of upturned T section and
15,320 785,320 the backbone be of downwardly-directed U section, the
stem of the T being received between the sides of the U, and the
securing clip reaching through the said stern and sides, thus

14. preventing detachment of the ledge portion.
If it is desired that the ledge portion shall be detachable, thus
permitting the ceiling or like boards to be dismounted without damage,
a detachable staple may be provided through which the securing clip
reaches in addition to reaching through the backbone, the legs of
which staple themselves reach through the ledge portion to the exposed
face thereof and are bent into position to hold the ledge portion in
operative position, but can readily be bent out of such retaining
position The said ledge portion may be formed with a trough to house
the 210 legs of the staple when they are in retaining position
Alternatively, this staple may be replaced by a spring clasp
comprising a base part which bears against the exposed face of the
ledge portion and spring arms which reach through an aperture in the
latter to embrace the securing clip which reaches through the
backbone.
In another construction in which the ledge portion of the runner is
detachable, a nut is vil mounted in the slot in the backbone through
which the securing clip reaches, and a headed screw is passed into
this nut from the exposed face of the ledge portion In this
construction, the backbone may conveniently be of the aforesaid
inverted U shape so that the fixing screw can reach into the space
between the sides of the U, and the ledge portion may have two ribs on
its face to receive between them the lower edges of the 4 o backbone.
A tbree-part runner construction according to the invention may
comprise a backbone of inverted U formation as aforesaid, a ledge
portion like the one shown in Specification No 663,109, mentioned
above, which is in two parts, one of which receives the ceiling or
like boards and interengages with the other part by laterally directed
ribs and channels, which other part overlaps the o) backbone and is
connected thereto by the securing clip.
For a more complete understanding of the invention there will now be
described, by way of example only and with reference to the
accompanying drawings, various constructions of securing means
according to the invention It is to be understood, however, that the
invention is not restricted to the precise constructional details set
forth.
tio In these drawings:Figure 1 is a sectional view of one
construction, Figure 2 is a perspective view of the runner shown in
Figure 1:
Figure 3 is a view corresponding with 65 Figure 1 of a modified
construction; Figure 4 is a similar view of another construction;
Figure 5 is a sectional view of a construction which lends itself to
easy dis 70 mounting of the ceiling or like boards; Figure 6 is a
section on the line 6-6 of Figure 5; Figure 7 is a sectional view

15. showing another construction which lends itself to easy 75 dismounting
of the ceiling or like boards; Figure 8 is a section on the line 8-8
of Figure 7; Figures 9 and 10 are views corresponding in part with
Figure 8 but showing the posi SE) tions occupied by certain of the
parts during the stages in the assembly; Figure 11 is a sectional view
showing a further construction which lends itself to easy dismounting
of the ceiling or like 85 boards; Figure 12 is a detail view of one of
the parts shown in Figure 11; and Figure 13 is a view corresponding
with Figure 4 but showing a different form of 9,0 runner.
Like reference numerals indicate like parts throughout the drawings.
Referring firstly to Figures 1 and 2, the securing means therein shown
are adapted to 9-5 hold the ceiling or like boards permanently in
position That is to say, when the components of a ceiling or the like
have been assembled, individual boards thereof cannot be dismounted
without distorting or l OM) damaging the boards and/or the securing
means Two ceiling boards are shown at and 11 and they are supported by
a runner which is bent from sheet material and has two ledges 12 and
13 and a backbone 14 105 of double thickness The boards 10 and 11 are
held against the ledges 12 and 13 by a wire clip of cranked formation
The middle portion 15 of its length reaches right through the backbone
14 at a position between the 110 opposed faces 16 and 17 of the boards
when the latter are resting upon the ledges 12 and 13 The end portions
18 and 19 of its length closely overlie the faces 17 of the boards.
The backbone 14 is formed with a slot 20 115 (see particularly Figure
2) to receive the cranked securing clip This slot 20 is eloneated in
the direction of the length of the runner to permit the passage of a
crank 21 or 22 in the clip prior to the latter being 120 turned into
operative position When in the latter position, viz the position shown
in Figure 1, the cranks 21 and 22 prevent dislodgement of the clip As
will be seen more particularly from Figure 1, this slot 20 is 1 '25
situated at a position between the opposed faces 16 and 17 of the
boards when the latter are resting on the ledges 12 and 13 At the
junctions of the part 18 and 21, and 19 and 785,320 22 respectiveiy of
the clip, extensions 23 and I 24 are provided As will be seen from c
Figure 1, these extensions reach beyond the i face 17 of the boards
and provide a finger 1 3 grip to facilitate turning the clip into
operative position and holding it during board assembly.
In Figure 3 a form of runner is shown which is made by rolling,
extrusion or castle ing It is of upturned T section, the rib 25 being
integral with the ledges 12 and 13.
The rib 25 is slotted in a manner similar to that shown at 20 in
Figure 2 There is shown at 26 a backbone which is separately formed
1,3 and consists of a single thickness of strip material The portion
15 of the securing clip passes through a slot in the strip and serves

16. to connect the backbone to the leg of the runner If desired the upper
edge 2 ( of the backbone 26 may be bent to form an angle section and
so to provide greater stiffness.
In the construction shown in Figure 4 the ledge portion of the runner
is of upturned 23 T section as in Figure 3 and the backbone 27 is
formed separately, being of downwardly-directed U section and being
attached to the rib 25 of the ledge portion by the securing clip.
3 o Figures 5 and 6 show a construction which permits the ceiling or
like boards 10 and 11 to be dismounted without damage A detachable
staple 28 is provided which is initially made in the formation shown
in chain lines in Figure 6 The securing clip, in addition to reaching
through the backbone 27, also reaches through the staple 28 The legs
of the staple reach through an aperture in the ledge portion of the
runner to the exposed face thereof and are bent, as shown in Figure 6,
to retain the ledge portion of the runner in operative position
Hlowever the legs of the staple can readily be bent out of such
retaining position if it is desired to dismantle the ceiling board or
like assembly.
The ledge portion of the runner is of sheet formation affording ledges
12 and 13 for the boards and a trough 29 to house the legs of the
staple 28 when they are in retaining position The staple 28 can be
introduced from below, as seen in Figures 5 and 6, at an upwardly
sloping angle, one limb on each side of the securing clip where this
passes through the slot 20 in the backbone 27.
-5 a When the staple has more than half of its length reaching past
the clip it will topple and fall into the position shown in Figure 6
with the two legs depending from the loop of the staple which latter
is suspended from i 10 the securing clip The ledge portion of the
runner will then be moved up into position and the legs of the staple
bent as shown in Figure 6 to retain the ledge portion in place.
A somewhat similar construction is shown 1 A in Figures 7 to 10 but
here a spring clasp replaces the stapie 28 This spring clasp comprises
an elongated base part 30 which is intended to be housed in the trough
29 of the ledge portion of the runner Spring arms 31 and 32 reach
through an aperture in the 70 trough 29 to embrace the portion 15 of
the securing clip The operative retaining position of the parts is
shown in Figures 7 and 8, and Figures 9 and 10 show stages in the
assembly of the parts The ledge portion 75 of the runner with the
spring clasp in place is firstly moved into position for the
extremities of the arms 31 and 32 to embrace the portion 15 of the
securing clip as shown in Figure 9 Further movement of the parts 80
brings them to the position shown in Figure and finally into the
position shown in Figure 8 If necessary by applying a pull the parts
may be dismounted.

17. In the construction shown in Figures 11 85 and 12 the ledge portion of
the runner has two ribs 33 and 34 which receive between them the lower
edges of the backbone 27 A nut 35 is mounted in the slot in the
backbone and a headed screw 36 is passed into this 9 nut from the
exposed face of the ledge portion of the runner The screw 36 reaches
into the space between the sides of the U shaped backbone 27 Any
preferred form of nut 35 may be employed In the construc (tion shown
this nut is a portion of a thin sheet, and is formed with a central
perforation 37 to engage the threads of the screw 36 The perforation
37 is surrounded by two lugs 38 which are partly severed from 100 the
main body of the nut 35 and are bent out of the general contour of the
nut so as to afford scope for contracting on to the screw 36 as the
latter is tightened The construction shown in Figures 11 and 12
permits the 105 ceiling or like boards to be readily dismounted if
necessary.
Figure 13 shows a three-part runner construction and comprises a
backbone 27 bent from sheet, and a ledge portion like the one 110
shown in Specification No 663,109 This ledge portion is in two parts,
one of which provides ledges 12 and 13 to receive the ceiling or like
boards and has a laterally directed rib 39 forming a channel The other
part of 115 the ledge portion reaches into the backbone at 40 to be
connected thereto by the securing clip, and has a laterally directed
rib 41 to enter the channel afforded by the rib 39 and also afford a
channel to receive said rib 39 120 It is to be understood that the
invention is not restricted to the precise constructional details set
forth.
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* GB785321 (A)
Description: GB785321 (A) ? 1957-10-23
Convertible bed settee

18. Description of GB785321 (A)
PATENT SPECIFICATION
Inventor:-WIILLIAMV JOSEPH HALL.
Date of filing Complete Specification: April 20, 1955.
Application Date: Feb 14, 1955 No 4298/55.
Complete Specification Published: Oct 23, 1957.
Index at Acceptance: -Clags 52 ( 2), Bl B. International
Classification:-A 4 "c.
COMPLETE SPECIFICATION.
Convertible Bed Settee.
We, STEEL & Co MPAY LIMITED, of 15 Robinson Road, Cambridge Heath,
London, E.2, a British Company, do hereby declare the invention, for
which we pray that a patent may be granted to us, and the method by
which it is to be performed, to be particularly described in and by
the following statement:-
The present invention relates to seats which are convertible into
beds.
According to the invention a convertible seat comprises a seat frame
and a back rest frame each of generally rectangular shape and pivoted
one to the other for swinging about an axis extending longitudinally
of the frames, from a " seat " position in which the back-rest frame
extends upwardly from the seat frame, to a " bed " position in which
the two frames extend substantially horizontally in co-planar relation
to form a bed of normal full length in the longitudinal direction of
the frames, and a wire mattress supported by, and extending
continuously across the two frames and adapted to flex upon relative
pivotal movement thereof, the said mattress providing an uninterrupted
resilient support extending over substantially the whole area enclosed
by the frames when in the extended co-planar position.
According to a further feature of the invention, the back rest frame
is provided with folding legs for supporting the frame in the " bed "
position and a linkage connects the folding legs to the seat frame so
that upon the backrest being swung upwardly to the "seat" position the
legs are automatically folded to lie against the back-rest frame.
According to a still further feature of the invention the said linkage
serves releasably to secure the backrest in the upright ' seat"
position.
lPrice 3 s 6 d l One embodiment of the invention will now be described
with reference to the accompanying drawings in which:Figure 1 is a
front elevation of the framework of a convertible seat according to
the invention, the framework being shown in the folded or " seat "

19. position; Figure 2 is an end elevation of the frameFigure 3 is a
section taken along the line III-III of Figure 1 but showing the
framework in the extended or " bed " position; and Figure 4 is a
partial end elevation of the framework drawn to an enlarged scale.
As will be seen from the drawings, the seat comprises a seat frame
indicated generally at 1 and a back rest frame indicated generally at
2 pivoted to the rear of the seat frame for angular displacement with
respect thereto from a generally upright position as shown in Figures
1 and 2, to a position substantially co-planar therewith as shown in
Figure 3.
The frames 1 and 2 are of generally elongated rectangular shape and
the pivotal axis of the frames extends longitudinally thereof.
The seat frame 1 is formed of a length of angle iron to provide a
U-shaped frame having a front member 3 curving at each end
respectively into an end member 4.
Secured to the front member 3 as by screws is a pair of legs 6 spaced
along the length thereof and each end member 4 has secured thereto
adjacent the rear end thereof as by welding, a tubular leg 7, the
respective legs 7 being braced by tubular stretchers 8 by extending
therebetween longitudinally of the frame 1 The front legs 6 and the
rear legs 7 are provided with castors 9 and the seat frame is thus
supported in a substantially horizontal position for movement over a
floor or like surface.
785,321 785,321 The back rest frame 2 is also formed of a length of
angle iron to provide a U-shaped frame having a top member 10
extending lengthwise of the seat and curved at each end respectively
into an end member 11 pivoted at its end as at 12 to the rear end of
the corresponding end member 4 of the seat frame 1 permit the back
rest frame to be swung from the generally upright position of Figures
1 and 2 to the horizontally extended position of Figure 3.
A wire mattress 13 is secured in known manner to the front member 3
and end members 4 of the seat frame and to the top member 10 and end
members 11 of the back rest frame so that the mattress extends
continuously across the two frames when the frames are in the extended
position and bends along the pivotal axis of the frames when the back
rest frame is swung upwardly to the upwardly extending or " seat "
position As will be apparent from Figure 3, when the frames are in the
extended or "bed " position, the mattress is freely supported solely
by the frame members and provides an uninterrupted resilient support
extending over substantially the entire area enclosed by the frames.
Upholstered cushions indicated in broken line at 14 and 15
respectively in Figures 2 and 3 are supported upon the seat frame and
back rest frame portions of the mattress 13, the said cushions
extending the full length of the respective frames and being of a

20. con3,5 struction suitable for use as mattresses when the frames are in
the extended "bed" position The length of the seat and backrest frames
is that of a normal full-size bed and the width of the frames is such
that when the frames are in the extended position, the cushions 14 and
15 placed side by side in engagement with each other provide a normal
double-bed sized mattress.
In order to support the back rest frame in the horizontal position, a
floor engaging support in the form of a U-shaped tubular member 16 has
the end of each leg thereof pivotally secured respectively as at 17 in
a bracket 18 secured as by welding to the end frame members 11
intermediate the length thereof, the member 16 thus extending
longitudinally of the back rest frame 2 for pivotal movement from a
position lying against the frame (Figures 2 and 4) to a floor engaging
position extending downwardly therefrom (Figure 3) the length of the
legs of the U-shaped member 16 being such that in the latter, floor
engaging position, the member supports the back rest frame in a 601
horizontal position substantially coplanar with the seat frame 1.
In order to effect the said pivotal movement of the member 16
automatically as the back-rest frame is swung downwardly from 6., the
upright position a link 19 is pivotally connected at each end
respectively to the member 16 and to the end member 4 of the seat
frame The link 19 is in the form of a rod the ends of which are turned
at right angles to the rod, one of said ends engaging 70 as at 20 in
an aperture in a lug 21 on the seat frame end member 4 and extending
rearwardly from the pivotal connection 12 of the seat and back-rest
frames, the other end of the link 19 extending as at 22 through an 75
aperture in the leg of the U-shaped member 16.
The length of the link 19 and the respective pivotal connections
thereof to the seat frame member 4 and to the U-shaped member 16 80
are such that when the back rest frame is in the upright position, the
member 16 is constrained to lie against the back rest frame as shown
in Figures 2 and 4, and when the back rest frame is swung downwardly
to the 85 horizontal position, the member 16 is caused to pivot to the
floor engaging position to support the back rest frame thereon as
shown in Figure 3.
As will be more clearly seen in Figure 4, 9 t O by reason of the
rearwardly extending lug 21, the link 19 extends upwardly and
forwardly therefrom when the back-rest is in the upright position, the
link thus forming a strut which releasably locks the back-rest 95
frame in the upright position since the link swings over dead centre
with respect to the pivotal connection of the U-shaped member 16 to
the back-rest frame 2 and in order to pivot the back-rest frame
downwardly to the 100 extended position, it is first necessary to
swing the U-shaped member 16 rearwardly from the back-rest frame to

21. release the locking action of the link 19.
In order to avoid inadvertent rearward 105 swinging movement of the
member 16, however, a latch 23 (Figure 4) is pivoted on the back-rest
end frame member 11 and is adapted to engage over the end 22 of the
link 19 which extends through the leg of the 110 member 16, thereby
releasably to secure the member 16 in the folded position lying
against the back-rest frame.
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* GB785322 (A)
Description: GB785322 (A) ? 1957-10-23
Improvements in or relating to multi-stage fluidised reactors
Description of GB785322 (A)
A high quality text as facsimile in your desired language may be available
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DE1020608 (B)
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The EPO does not accept any responsibility for the accuracy of data
and information originating from other authorities than the EPO; in
particular, the EPO does not guarantee that they are complete,
up-to-date or fit for specific purposes.
COMPLETE SPECIFICATION.

22. Improvements in or relating to Multi-Stage Fluidised Reactors.
We, THE NATIo4L SMELTING COMPANY
LIMITED, whose registered office is at 9
Basinghall Street, E.C.2, in the City of
London, a Company registered under the laws of Great Britain, do
hereby declare the invention, for which we pray that a patent may be
granted to us, and the method by which it is to be performed, to be
particularly described in and by the following statement
This invention relates to multi-stage fluidised reactors of the kind
in which a plurality of fluidised beds are mounted, one above the
other, the flow of fluidised material being from an upper to a lower
bed.
This flow has hitherto been achieved by means of an internal passage
or passages.
With such an arrangement if a blockage occurs the passage or passages
can be cleaned only after shutting down and opening up of the reactor.
The present invention consists of a multistage, fluidised reactor of
the kind described in which a passage is provided for the fluidised
material to pass out of the reactor from an upper bed and to pass back
into the reactor to a lower bed, access means being provided for
cleaning the passage from outside the reactor.
Means may also be provided for cooling or heating or otherwise
treating the fluidised material outside the reactor between the
stages.
It is also possible to analyse material taken from the passage and to
add amounts of other material to the fluidised material when in the
external passage.
Furthermore the pipes forming the passage may be readily replaced.
Also valves may be placed in them and the rate of flow controlled or
temporarily stopped. This means of control is particularly useful when
the reactor is being started up.
The invention will be further described with reference to an
embodiment shown in the drawing accompanying the Provisional
Specification which is a vertical section of a multi-stage fluidised
reactor.
The reactor comprises an outer cylindrical casing 1 having three
horizontal perforated plates 2, 3 and 4, mounted there-across to form
beds for the fluidised material while permitting the upward flow of
gas. The casing has a closed upwardly expanding frusto-conical part 5
at the top and a closed downwardly contracting conical part 6 at the
bottom. A pipe 7 provides a gas access passage at the bottom.
From just above the perforated plate 3 a pipe 8 is led outside the
casing 1 at a downward angle of 49" thereto in the vertical section
and this joins a further pipe 9 at a downward angle of 61Q to the

23. horizontal which leads back into the casing and is then bent
downwardly to give a vertical portion of substantial length which
terminates just above the perforated plate 4.
A pipe 10 similar to the pipe 8 is provided, leading out of the casing
from above the perforated plate 2, and connecting to a pipe 11 similar
to the pipe 9 and leading back into the casing and terminating just
above the perforated plate 3.
A pipe 12 is provided leading from outside the casing to just above
the perforated plate 2 for feeding-in material to be fluidised and a
pipe 13 leading from above the perforated plate 4 for removing the
fluidised material from the lowermost bed.
The pipes 8, 9 and 10, 11 have removable end caps 15, 16 and through
the caps 16 there operate valve members 17 which engage with a seating
in the respective pipes 9, 11.
9 gas outlet 14 is provided at the top of the part 5.
This three-st-age reactor is designed to produce aluminium fluoride by
reaction between dry aluminium hydroxide ancl either pure hydrogen
fluoride or a misture of dry air and hydrogen fluoride. Most of the
dehydration and a certain amount of reaction takes place inside the
top bed. In the second bed dehydration is completed and most of the
reaction - takes place. Reaction is completed in the bottom stage. Ill
the aluminium hydroxide charged into the system leaves the bottom of
the reaetor as aluminium fluoride containing 85O/o to 96 O of AIF3,
except for a small amount, which may be of the order of 2% of the feed
which is tarried by the exit gas through cyclones into a scrubber
system and recovered as wet aluminium hydroxide. The collection in the
eyelones is returned to the reactor.
Various modifications may be made within the scope of the invention.
Thus the angle of inclination of pipes 8 and 10 to the horizontaI is
not necessarily 49 this angle being fixed, in accordance mith the
physical properties of the reactants, so that the material will flow
freely.
Instead of three stages in the reaetor, two, four, five or six for
example might be used.
In the embodiment described all the fluidised beds have the same
diameter.
Sometimes, in order to obtain suitable fluidizing velocities, it will
be necessary to have different areas of beds for different stages. The
fluidizing velocities required may be different in the different
stages, owing to differences of gas temperature, and composition (and
therefore density) of the solid, as between one stage and another.
Further, even if the same velocity is required, the volume of gas
generated by the reaction may be different from the volume of gas
centering into the reaction; for instance, if anhydrous alumina were

24. used instead of ahllllinium hydroxide in the example less water vapour
would be generated in the top stage and it might be found necessary to
have the bed in tire top stage of a lesser diameter than the lower
beds. Above the top stage, the upwardly expanding part. as shown in
the drawing, is optional.
The manufacture of aluminium fluoride i,', of course, only an example
of a reaction that can be carried out in the reactor. It could be used
for any reaction that can be carried out in fluidised beds.
What a--c claim is
1. A multi-stage fluidized reactor of the kijid described in which a
passage is provided for tile fluidised material to pass out of the
reactor from an upper bed and to pass baeli into the reactor to a
lower bed, access means being provided for deanine the passage from
outside the reactor.
2. A multi-stage fluidised reactor as claimed in Claim 1 in which the
passage comprises a pipe led outside the reactor from one iluidised
bed at downward angle between the horizontal and the vertical and
joined to a further pipe which leads baelS into the reactor at a
downward angle between the horizontal and the vertical.
3. A multi-stage fluidised reactor as claimed in Claim' in which the
further pipe inside the reactor is bent downwardly to give a vertical
portion of substantial length which terminates in the lower bed.
4. A multi-stage fluidised reactor as claimed in Claims 2 or 3 in
which the pipes have removable end caps.
O. A multi-stage fluidised reactor as claimed in Claim 4 in wilich a
valve member extends with a seating in the pipe.
6. A multi-stage fluidised reactor, substantially as described and
shown in the draping accompanying the Provisional
Specification.
PROVISIONAL SPECIFICATION.
Improvements in or relating to Multi-Stage Fluidised Reactors.
We, ThE NATIONAL SMELTING COMPANY LIMITED, whose registered office is
at 9,
Basinghall Street, B.C .2, in the City of
London, a Company registered under the laws of Great Britain, do
hereby declare this invention to be described in the following
statement :
This invention relates to multi-stage fluidised- reactors of the kind
in which a plurality of ffuidised beds are mounted, one above the
other, the flow of fluidised material being from an upper to a lower
bed.
This flow has hitherto been achieved by means of an internal passage
or passages.
With such an arrangement if a blockage occurs the passage or passages

25. can be cleaned only after shutting down and opening up of the reactor.
The present invention consists of a multistage fluidised reactor of
the kind described in which a passage is provided for the fluidised
material to pass out of the reactor from an upper bed and to pass back
into the reactor to a lower bed, access means being provided