5131 5135.output

* GB785538 (A)
Description: GB785538 (A) ? 1957-10-30
Improvements in or relating to transistor circuits
Description of GB785538 (A)
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1 -j I I
PE S -PE ' AT PATENT SPECIFICATION ' > Date of Application and filing
Complete
Specification: Nov 27, 1953.
Application made in Netherlands on Dec 1, 1952.
(Divided out of No 785537).
Complete Specification Published: Oct 30, 1957.
Index at Acceptance:-Class 40 ( 6), T.
International Classification:-HO 3 f.
COMPLETE SPECIFICATION
Improvements in or relatin ts T 785,538 No 20864/53.
SPECIFICATION NO 785,538
In tne headilng on pane 1, for ago 2 ose 4/53 N read 1 NO 20864/57 "'
T Hl E PATENT OFFICE, 25th November 5 1957 ine invention has for its

object to provide improved transistor circuits for the above purpose.
The invention comprises a mixing circuit which embodies a transistor
provided with at least one emitter electrode, at least one collector
electrode, and two base electrodes and wherein a first source of
oscillations is connected between a said emitter electrode and one or
both of said base electrodes, and a second source of oscillations is
coupled to an input circuit which includes at least one of the said
base electrodes, the circuit being so proportioned that one or each of
the said sources is discoupled from oscillations emitted by the other
said source.
In order that the invention may be readily carried into effect,
embodiments thereof will now be described by way of example with
reference to the accompanying diagrammatic drawing in which:Figure 1
'shows a transistor push-pull modulator circit, Figure 2 shows
characteristic curves for assistance in explaining the operation of
the circuit shown in Figure 1.
Figure 3 is a modification of the transistor modulator shown in Iigure
1, ind Figure 4 shows schematically a point-contact transistor for use
in the circuit shown in lPrice 3 s 6 d JQ; DB 00840/1 ( 15)/3606 150
11/57 R _ i,,,,}tn, p zone in this 60 way transistor action is
obtained both between the electrodes e, bl and c and between the
-electrodes e, b 2 and c Thus the electrodes e, b 1 and b 2 act as
input electrodes andthe electrode c acts as an output electrode 65 The
circuit of the emitter electrode e includes a source V 1 of
oscillations, and oscillations from a source V 2 are supplied through
a push-pull transformer 5 to the two base electrodes bl and b 2 so
that these carry potentials with respect to 70 the emitter electrode
which are opposite in -phase.
In this manner a modulation product of the input oscillations V 1 and
V 2 is produced across an output impedance 6 which is tuned 75 to a
frequency of the modulation product and included in the collector
circuit If the bridge is properly balanced, however, the diagonals
embodying the sources V 1 and V 2 will be discoupled fom one -another
in 80 respect of the fundamental-frequencies of these -sources,
although the modulation products will pass through both diagonals.
Figure 2 shows ciaracteristics -for those values of the voltages V,
and V 2 at which a 85 constant emitter current i 4 flows to the
emitter electrode e Since the currents to the base electrodes b, -and
b 2 are small in comparison -with the emitter current ie, the same
curves also hold good substantially for those values 90 PATENT
SPECIFICATION
Dote of Application and filing Complete Specification: Nov 27, 1953.
785 X 9538 No 20864/53.
Application made in Nethetlands on Dec 1, 1952.

(Divided out of No 785537).
L Complete Specification Published: Oct30, 1957.
Index at Acceptance:-Class 40 ( 6), T.
International Classification:-HO 3 f.
COMPLETE SPECIFICATION
Improvements in or relating to Transistor Circuits We, PHILIPS
ELECTRICAL INDUSTRIES LIMITED of Spencer House,, South Place,
Finsbury, London, E C 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:-
This invention relates to transistor circuits for mixing two electric
oscillations In known circuits two sources of oscillations have been
jointly operative between the emitter electrode and base electrode of
a transistor but this arrangement has the disadvantage that each
source reacts directly upon the other.
The invention has for its object to provide improved transistor
circuits for the above purpose.
The invention comprises a mixing circuit which embodies a transistor
provided with at least one emitter electrode, at least one collector
electrode, and two base electrodes -and wherein a first source of
oscillations is connected between a said emitter electrode and one or
both of said base electrodes, and a second source of oscillations is
coupled to an input circuit which includes at least one of the said
base electrodes, the circuit being so proportioned that one or each of
the said sources is discoupled from oscillations emitted by the other
said source.
In order that the invention may be readily carried into effect,
embodiments thereof will now be described by way of example with
reference to the accompanying diagrammatic drawing in which:Figure 1
shows a transistor push-pull modulator circuit, Figure 2 shows
characteristic curves for assistance in explaining the operation of
the circuit shown in Figure 1.
Figure 3 is a modification of the transistor modulator shown in Figure
1, and Figure 4 shows schematically a point-contact transistor for use
in the circuit shown in lPrice 3 s 6 d 4 l;__p Figure 1.
The transistor shown in Figure 1 is a.
junction transistor with zones N and p having conductivities of
opposite types It is provided with an emitter electrode e, two
symmetrical 50 base electrodes bl and be which enable a potential
gradient parallel to the n-p boundary to be set up, and a collector
electrode c The base electrodes b, and b 2 are connected to a single p
zone, whose thickness is smaller than that 55 of the characteristic
diffusion length of the charge carriers present in minority in this p

zone, and the emitter electrode e and the collector electrode c are
connected to two different N zones adjoining the p zone In this 60 way
transistor action is obtained both between the electrodes e, b, and c
anrd between the electrodes e, b, and c Thus the electrodes e, bl and
b, act as input electrodes and the electrode c acts as an output
electrode 65 The circuit of the emitter electrode e includes a source
V 1 of oscillations, and oscillations from a source V, are supplied
through a push- pull transformer 5 to the two base electrodes b, and b
2 so that these carry potentials with respect to 70 the emitter
electrode which are opposite in phase.
In this manner a modulation product of the input oscillations V 1 and
V 2 is produced across an output impedance 6 which is tuned 75 to a
frequency of the modulation product and included in the collector
circuit If the bridge is properly balanced, however, the diagonals
embodying the sources V 1 and V 2 will be discoupled from one another
in 80 respect of the fundamental frequencies of there sources,
although 'the modulation products will pass through both diagonals,
Figure 2 shows characteristics for those values of the voltages V 1
and V 2 at which a 85 constant emitter current 4 flows to the emitter
electrode e Since the currents to the base electrodes bl and b 2 are
small in comparison with the emitter current i 4, the same curves also
hold good substantially for those values 90 of the voltages V 1 and V
2 at which a constant collector current 4 flows from the collector c.
When the voltage V 1 oscillates at a frequency fl and the voltage V 2
oscillates at a frequency f 2, the emitter currents and collector
currents include modulation products of frequency (f 1 12 f 2), and
the current through the secondary winding of the transformer 5
contains a modulation product of frequency (fhi 12) If, for example,
the signal V 1 is taken by way of selective means from the receiving
antenna of a radio receiver while the oscillation V 2 is supplied from
a local oscillator, a modulation product (f 1 -2 f 2) can be obtained
across the output impedance 6 without the local oscillation reacting
unduly on the antenna.
Figure 3 shows a further circuit in which the transistor element
comprises a mass p of one conductivity type interrupted by two thin
zones N of opposite conductivity type, the thickness of the zones N
again being smaller than the characteristic diffusion length of the
charge carriers present in a minority in the n zones One oscillation V
1, derived for example from a receiving antenna, is applied (by way of
a small part of the secondary coil shown, through a tapping) between
the emitter electrode e connected to one of the p zones and the base
electrode bl; and the other oscillation V 2, for example a local
oscillation, is applied between the emitter electrode e and the base
electrode b 2 associated with the second N zone, and the circuit is so

balanced (i e the tapping is so placed) that the arms containing the
sources of V 1 and V 2 are discoupled, so that neither of these
sources reacts on the other Under these conditions a modulation
product having, for instance, a frequency equal to the difference
between the frequencies of the oscillations from sources V 1 and V 2,
appears across a tuned output impedance 16 in the collector circuit.
Instead of a transistor of the junction type, a transistor of the
point-contact type and having two base electrodes may alternatively be
used in the circuit shown in Figure 1 Figure 4 is a plan view of such
a transistor The two ends of the transistor crystal, the whole of
which constitutes a base region, are connected to the two base
electrodes b, and b 2 and on the top of the crystal are placed an
emitter electrode e and a collector electrode c with the requisitely
close spacing, so that the line connecting the contact points of the
electrodes e and c extends substantially at right angles to the
direction of the electrical field F which is produced in the
neighbourhood of the electrodes e and c when a potential difference is
set up between the electrodes bl and b 2.
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* GB785539 (A)
Description: GB785539 (A) ? 1957-10-30
Improvements in and relating to earth leakage detection and/or indication
systems
PATENT SPECIFICATION
Date of filing Complete Specification: Nov 2, 1953.
Application Date: Sept 12, 1952 No 23029152.

Index at Acceptance:-Class 38 ( 5), B 1 R' 4 A 1: 14: 180,, B 2 A 2,
K( 1 B:17: 20: 21).
International Classification:-H Olh H 02 d.
COMPLETE SPECIFICATION.
Improvements in and relating to Earth Leakage Detection and/or
Indication Systems.
We, THE SIEMENS & GENERAL ELECTRIC RAILWAY SIGNAL COMPANY LIMITED, a
British Company, now of East Lane, Wembley, Middlesex, formerly of
Caxton House, Tothill Street, Westminster, London, S.W 1, and THOMAS
DOUGLAS AUSTIN and HUBERT JOHN NAPIER RIDDLE, both British Subjects,
of The Siemens & General Electric Railway Signal Company Limited, East
Lane, Wembley, Middlesex, 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 earth leakage detection and/or indication
arrangements for electric supply systems of the kind in which no
supply conductor is normally earthed.
In such a system the electrical potential between earth and a supply
conductor is of course affected not only by resistive earth leaks of a
relatively constant magnitude but also by transient inductive surges
and capacitative changes on change of load or on supply network
switching changes The consequent transient changes in potential and
leakages are often of greater magnitude than the maximum relatively
constant leakage that can be tolerated with the result that the
sensitivity of any associated earth leakage detection and/or
indication device has correspondingly to be reduced in order to avoid
unnecessary indication or even protective action.
The object of the present invention is to provide an improved earth
leakage detection and/or indication arrangement which is not so
subject to the above-mentioned disadvantage and which at the same time
does lPrice 3 s 6 d l not involve the physical insertion of a circuit
element in series with a supply conductor.
According to the present invention, an earth leakage detection and/ or
indication system for an electric supply system in which no supply
conductor is normally earthed comprises a condenser arranged
repeatedly and alternately to be connected either so that any earth
leakage from an associated supply conductor causes a charge to be
supplied to the said condenser or so that any charge developed on said
condenser is delivered to a charge detection or indication means.
In a preferred embodiment in accordance with the invention iterative
switching means are arranged either to connect the condenser so that a
charge would be supplied thereto in the event of an earth leakage from

an associated supply conductor or to cause the discharge of any such
developed charge through one winding of a multi-wound relay associated
with indication means, the arrangement being such that the multiwound
relay is normally held operated by current in one winding, the flux
from which is opposed by flux developed in a second winding when any
such developed charge on the condenser is dissipated therethrough, the
relay being released when the charge from said condenser exceeds a
predetermined value and thereby causes operation of the indication
means.
Four arrangements in accordance with the invention will now be
described by way of example with reference to the accompanying
diagrammatic drawings The arrangements shown in Figures 1 and 2
respectively are concerned with the detection of earth leakage from
one side of a pair of direct current 7855539 supply leads neither of
which is normally earthed, and with the detection of earth leakage
from both sides of a similar pair whilst the arrangements shown in
Figures 3 a and 4 are concerned with the detection of earth leakage
from one or both sides respectively of an alternating current supply
over a pair of conductors.
In the arrangement shown in Figure 1 a multi-wound relay R has one
winding RW 1 permanently connected through a resistance HR between the
positive and negative sides of the supply line B and N A second
winding RW 2 of the multi-wound relay is connected on one side to one
plate of a condenser Q and to earth whilst the other end of the
winding RW 2 is connected to a changeover contact ITI of a relay IT of
an iterative circuit The second plate of the condenser Q is connected
through the said contact I Ti of the relay IT in the iterative circuit
in such a way that in one position of the contact I Ti the condenser Q
is connected to discharge through the second winding RW 2 of the
multi-wound relay R and in the other position of the contact the
condenser Q is connected between the positive supply line B and earth.
The repeated changeover of the said iterative contact I Ti may be
achieved in any suitable manner but is preferably achieved by making
the relay IT part of an iterative relay circuit as shown The relay IT
comprises two windings ITWI and ITW 2 which can be considered as
connected in series across a condenser QR, one side of the direct
current electric supply N being connected to one plate of the
condenser QR and also connected to one end of that relay winding ITW 1
The second contact IT 2 of the said relay IT is arranged when closed
to connect the other side B of the said direct current electric supply
to the common connection between the said two series connected
windings ITWI and ITW 2.
In operation the contact IT 2 will in one position connect the
condenser QR through winding ITW 2 to the positive supply line B for

one half second so that charging current to the condenser flows
through winding ITW 2 Simultaneously current also flows through the
winding ITWI and the resistance VR In the other position the condenser
QR is discharged of any charge developed thereon through both windings
ITWI and ITW 2 of the multi-wound relay IT for the next successive
half second Whilst the contact IT 2 is making the connection to the
positive supply line B, the currents in the winding ITW 2 and ITW 1
are in opposite directions As the charging of the condenser QR
proceeds, the current in the windinc ITW 2 decreases until it reaches
a value at which the flux developed in the winding ITW 1 predominates
and causes the relay IT to operate and open the contact IT 2.
The relay IT is now held operated by the discharge current from the
condenser flowing through the two windings ITW 1 and ITW 2 in series
70 Eventually the condenser QR is discharged to such an extent that
the current through the windings ITW 1 and ITW 2 can no longer hold
the relay operated On release, the contact IT 2 again causes con 75
nection to the supply line B so that the cycle recommences.
It will be appreciated that the timing period can be varied by
variation of the resistance VR, a suitable time being of the 80 order
of one-half second.
The value of the resistance HR in series with the first winding R Wl
of the multiwound relay R is such that the relay is normally held
operated (i e in the absence 85 of earth leakage from the line N).
If, however, an earth leakage develops from the negative supply line
N, it will be appreciated that when the condenser Q is next connected
to the positive supply line B 90 for the cyclic period of closing of
the contact ITI which is preferably of the order of one-half second,
it will receive a charge the magnitude of which will be dependent on
the magnitude of the earth leakage 9 a current from the negative
supply line N, since it is then effectively connected across the
resistive leakage path In the next successive connection of the
condenser Q to the second winding RW 2 of the multi 100 wound relay R,
the charge developed across the condenser Q is discharged through this
second winding RW 2 and the connection of the winding RW 2 is in such
a sense that the flux of the winding RW 2 opposes the 105 flux
developed in the first holding RW 1 winding If the magnitude of the
former flux is sufficiently great then the holding flux in the core of
the relay R will be momentarily reduced or neutralised and the 110
relay R will release, the normal current through the first winding RW
1 being only sufficient to hold the relay R energised but not to
operate the relay R from the released condition Contacts RI of the
multi-wound 115 relay R are accordingly closed to cause the operation
of, for example, a signal light S or alarm means to give an indication
that the earth leakage from the negative side of the supply has

exceeded a predetermined 120 value.
It will be appreciated that in contradistinction to earlier earth
leakage arranenemcnts, since the charge developed on the condenser Q
is integrated over the charge period 125 transient disturbances on the
supply line N will have a minimum effect on the charne developed
across the condenser O Accordingly the sensitivity of the detection
arrangements can be more closely related to the 130 785,539 the
contact then completes a lamp indication displaying red R.
Test buttons N and B are provided for the purpose of applying a
deliberate earth leak through ballast resistances ZTN and 70 ZTB
respectively, in order that the equipment may be checked for
satisfactory operatioi The ballast resistances ZTB and ZTN are of such
a value that they pass a current less than the maximum permissible
leakage 75 current.
In the third arrangement in accordance with the invention and as shown
in Figure 3, the earth leakage detection and indication is applied to
a two wire NX and BX alternat 80 ing current supply of which neither
side is normally earthed In this arrangement, as in previous cases,
there is associated a condenser changeover contact IT 1 of an
iterative relay circuit (not shown) but of similar 85 nature as the
iterative relay circuit shown in Figures 1 and 2 and a multi-wound
relay BXT and, as in the previous arrangements, the multi-wound relay
BXT is normally held operated by current through a resistance 90 NHR
and a first winding BXTW 1 which in this case is derived across a
bridge-connected rectifier network supply S from a transformer T, the
primary of which is connected between the two supply leads NX and BX
95 The second winding 1 BXTW 2 of the multiwound relay BXT has, as
previously described, a condenser Q which is either connected in
series with it through changeover contact I Tl of the iterative relay
or is open 100 circuited while the said condenser Q is connected at
the changeover contact so that it receives a charge in the event of an
earth leakage.
The condenser Q is arranged to be sup 105 plied with direct current
from a bridgeconnected group of rectifiers GR arranged across the
secondary of a transformer TF 1, the primary of which is connected
between earth and through a second contact IT 2 of 110 the iterative
relay to one side of the supply so that earth leakage on the other
side of the supply will be detected The iterative relay contacts IT 2
are so arranged that the primary of the transformer TF 1 is only con
115 nected to the supply line while the condenser Q is connected
across the rectifier bridge GR at contact ITI.
It will be appreciated, however, that with such an arrangement, the
condenser Q will 120 be charged not only by a resistive earth leak but
also by the permanent capacitative leak.

In some crvnmntances this may be a disadvantage.
Accordingly the disadvantage is overcome 125 by providin r that the
bridge-connected rectifiers GR arranged to supply charging current on
earth leakage to the condenser Q, are connected to the secondary of
the first transformer T Fl already mentioned, the primary 130 value of
earth leakage which it is required to detect.
Finally, after operation of the multi-wound relay R on detection of an
earth leakage, the relay R can be reset by temporarily
short-circuiting the resistance HR in series with its first winding
for example by means of a manual push-button "Reset".
The arrangement shown in Figure 2 of the drawings provides a system
for the detection and/or indication of earth leakage from both sides B
and N of a direct current supply line neither side of which is
earthed.
In this arrangement two units each comprising a multi-wound relay NGD
and BGD and a condenser QN and QB are employed.
Each unit is of the type already described in the first example and a
first coil NGDW 1 or BGDW 1 of each multi-wound relay is connected in
series with its own associated resistance NHR or BI-IR and
short-circuiting means "Reset N" or "Reset B" for that resistance,
between the supply lines Once again the value of current normally
flowing through each of the first windings NGDW 1 and BGDW 1 is such
that it is sufficient to hold the associated relay NGD or BGI)
operated but not to operate the relay if it has been released.
A single iterative relay circuit is provided, again of the type
previously described with reference to Figure 1 and correspondingly
referenced in Figure 2 The iterative relay IT is however provided with
two changeover contacts I Tl and IT 3, one associated with the
condenser QN for detecting leakage from the negative side of the
supply and the other associated with the condenser QB for detecting
leakage from the positive side of the supply The arrangements of the
two changeover contacts ITI and IT 3 are such that whilst one
condenser QB is connected to be charged by leakage, the other ON is
discharging through the second winding NGDW 2 of its associated
multi-wound relay and vice versa.
A sensitivity control is provided in association with each condenser
and the multiwound relay This sensitivity control comao prises a
variable resistance ZN or ZB connected across each condenser QN or QB
in such a way that each forms in conjunction with a leakage path when
it exists, a potentiometer of such proportions that sufficient voltage
drop can exist across the resistance ZN or ZB if the leakage path
resistance is low in comparison with ZN or ZB.
Each multi-wound relay NGD and BGD is provided with a changeover
contact NGD 1 or BODI which causes the energisation, when the relay is

operated, of a lamp, indication circuit, for example displaying a
green indication G, and if the relay is forced to release on
occurrence of an earth leakage, 785,539 of which is connected through
the second changeover contact IT 2 of the iterative relay to one side
NX of the supply and to earth, and to the secondary of a second
transformer TF 2, the primary of which is connected through a third
iterative contact IT 3 and an adjustable capacity CB between the two
alternating current supply lines.
With this arrangement, the adjustable capacity CB is initially varied
until its capacity has the sable value as the capacity of the supply
line (the leakage of which is to be detected), to earth, which will be
shown by no voltage being developed across the two series connected
secondaries of the transformers TFI and TF 2.
As in the arrangement described for the direct current supply, after a
leakage current has been detected, the equipment may be reset by
operation of the reset button RE which temporarily short-circuits the
resistance NHR and causes the current through the winding BXTW 1 to
increase to a value at which the relay BXT is energised and thereafter
holds-in The alarm system operated by the release of the relay BXT may
be of any suitable type: it may for example comprise a lamp
arrangement of the kind previously described.
The arrangement shown in Figure 4 provides a system for the detection
of earth leakage from either side NX or BX of an alternating current
supply system.
In this arrangement, two units each comprising a multi-wound relay
NXGD and BXGD and a condenser QNX and QBX are provided Each unit is of
the kind described in Figure 3 and a first coil of each multiwound
relay is connected in series with its own associated resistance ZNX or
ZBX; (having short-circuiting means "Reset NX" and "Reset BX"
connected thereacross) across the diagonal of a bridge connected
rectifier group S supplied from a transformer T connected between the
supply lines BX and NX As before the current through the first
windings is sufficient to hold the relay energised but is insufficient
to operate it, once it has been released Short circuiting of the
series resistance ZNX or ZBX by the associated reset button "Reset NX"
or "Reset BX" will however operate the relay after release.
An iterative relay circuit (not shown) of a similar nature to that
previously described is again provided The iterative relay comprises
four sets of changeover contacts ITI, IT 2, IT 3 and IT 4 Two sets IT
3 and IT 4 are respectively associated with the second windincs of the
relays NXGD and BXGD and alternately connect the respective condensers
QNX and QBX across -bridqe rectifier networks NGR and BGR and for
discharge through the associated winding of the associated relay The
arrangement of the two changeover contacts IT 3 and IT 4 are again

such that whilst one condenser QNX is connected to be charged by any
leakage current the condenser QBX is connected for discharge through
the associated; winding of the relay BXGD.
The bridge connected rectifiers NGR are connected across the series
connected secondaries of two transformers T Fi ants TF 2.
The primary of the transformer TFI is con 74 nected in one position of
the first changeover contacts ITI of the iterative relay between the
supply line BX and earth, so that leakage current from the line NX
will flow therethrough and, after rectification, effect 80 charging of
the condenser QNX The primary of the transformer TF 2 is arranged, in
one position of the changeover contact IT 2 to be connected between
the lines BX and NX through the variable condenser Ss NXCAP acting as
a capacity balance, in the manner previously described.
Similarly the rectifier group BGR is connected across the secondaries
of the transformers TF 3 and TF 4, the primaries of 90 which are
respectively connected between earth and supply line NX by contact IT
2 and between the lines NX and BX, through the capacity balance
condenser BXCAP, at contact ITI 95 The display arrangements (not
shown) can for example be similar to those shown in Figure 2.
It is to be understood that whilst in the arrangements shown above,
the cyclically 10 o repeated connection of the condensers which are
charged by leakage current is achieved by means of an iterative relay
circuit any other suitable iterative switching means, for example,
motor operated iterative switching 105 means, may be employed.
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* GB785540 (A)
Description: GB785540 (A)
No title available

PATENT SPECIFICATION 78 ^
g o IA Date of filing Complete Specification: M 1 arch 12, 1954.
Application Date: March 14, 1953 Nolo 7103/553.
Index at Acceptance:-Classes 69 ( 2), G(WA 1: 11 B:13 A: X); and 83 (
4), 1 H 4 (C 2: M).
International Classification:-B 23 j B 30 b.
Improvements in or relating to Hydraulically Operated Metal Working
Machines.
I, THOMAS CAMPBELL, a British Subject, of 75 Nevis Avenue, Belfast,
Northern Ireland, 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 relates to hydraulically operated metal working
machines, and especially presses, and hydraulic systems therefor.
Such machines comprise a member which is fixed and a member which is
movable relative to the fixed member in order to effect the pressing,
cutting or punching action.
Various hydraulic systems for operating said movable member have
hitherto been proposed, and the present invention is concerned with
systems which include two hydraulic rams acting on the movable member
at interspaced points In machines having such a system, there is a
tendency for one ram to move in advance of the other, should the load
on the movable member be unequally distributed Various proposals have
hitherto been made with a view to overcoming this disadvantage, but
these have involved the use of additional expensive apparatus and have
been relatively complicated so that such machines have been expensive
to manufacture, maintain and operate and have taken up too much space.
Thus an object of the present invention is to provide a hydraulic
system by which said disadvantage is overcome and which is of
relatively simple design, comparatively inexpensive to manufacture,
maintain and operate and highly efficient.
According to the present invention I provide a hydraulically operated
metal working lPrice 3 s 6 d 1 machine comprising a fixed member and a
member movable relative thereto and operated by a main hydraulic
system including two main hydraulic piston-and-cylinder assemblies
acting on the movable member at interspaced points, and an auxiliary
hydraulical system including a pair of cylinders and dduble-acting
pistons, the latter being connected to the said movable member at
interspaced points, and the compartment on one side of the piston in

one auxiliary cylinder being, in each case, in closed circuit with the
compartment on the other side of the piston in the other auxiliary
cylinder, in which in the auxiliary hydraulic system the compartments
on each side of the piston in one auxiliary cylinder are
interconnected by a pipe having a valve which when opened permits
adjustment of one auxiliary piston with respect to the other auxiliary
piston, said pipe being connected to one end of a further pipe which
at its, other end is adapted for connection to the main hydraulic
supply and which incorporates a combined stop and relief valve which
when opened permits the auxiliary cylinders to be filled or refilled
under pressure.
An embodiment of the invention will now be shown by way of example
with reference to the accompanying diagrammatic drawing which shows a
hydraulically operated press.
Referring to the drawing, the press consists generally of an upper
fixed member 1, a lower and vertically movable member 2.
and a hydraulic system including two hydraulic piston and cylinder
assemblies or rams generally indicated at 3 and 4.
The hydraulic system is formed by a main system which effects the
general operation of the movable member 2 and an additional or
auxiliary system of which the purpose will be later described.
5,540 7.5 58 ( 785,540 The main system consists of rams (proper) or
piston rods 5, 6 which at their upper ends are connected to the ends
of the member 2, and which at their lower ends are attached to pistons
7, 8 slidably mounted in cylinders 9, 10, the pistons 7, 8 being
double acting.
The lower compartments 11, 12 of the cylinders 9, 10 are
interconnected by pipe 13, and the upper compartments 14, 15 are
interconnected by pipe 16, and the pipes 13, 16 are connected to
supply and exhaust pipes 17, 18 through a control valve 19 and branch
pipes 20, 21 An adjustable pressure relief valve between the supply
and exhaust pipes 17, 18 is indicated at 22 The operation of the above
described main hydraulic system will be well understood and need not
be further described, it being sufficient to say that, by appropriate
adjustment of the control valve, the rams 5 and 6 can be raised or
lowered to operate the movable member 2.
The auxiliary hydraulic system consists of two cylinders 23, 24 and
two double-acting pistons 25, 26 located respectively on top of 2.5
the cylinders 3, 4 and sealed therefrom by gland members 27, 28 and
sealed at their top by further gland members 29, 30 The pistons 25, 26
are secured to the rams 5 and 6 and move therewith, and the upper
compartment 31 of the cylinder 23 is in closed circuit with the lower
compartment 32 of the cylinder 24 through a pipe 33 while the upper
compartment 34 of cylinder 24 is in closed circuit with the lower

compartment 35 of cylinder 23 through a pipe 36.
The compartments 32 and 34 of cylinder 24 are also interconnected by a
pipe 37 having a stop valve 38, the pipe 37 being connected to the
supply pipe 17 by a pipe 39 having a combined stop and relief valve
40.
The auxiliary cylinders 23, 24 are initially filled with hydraulic
fluid supplied from the main supply pipe 17 through pipes 39 and 37
with the valves 40 and 38 open, and these valves are then closed but,
if necessary are opened periodically in order to maintain the fluid
under a suitable pressure, for example, 100 lb per square inch While
the ,0 filling and maintaining of the fluid under pressure may not be
essential, it has in practice generally been found necessary in order
to fill the cylinders completely and has the added advantage of
keeping the gland ), packings tight.
When the valves 38 and 40 are closed and the control valve is operated
to raise the member 2, the pistons 25, 26, as aforesaid.
move with the piston rods or rams 5, 6 and 1) fluid is forced from the
upper compartments 31, 34, into the lower compartments 32 35
respectively Should, for any reason, such as an unequal load
distribution on the member 2, one ram say the ram 6 tend to move
upwards in advance of the ram 5 a correspondingly increased pressure
is applied to the fluid in the compartment 34 by the piston 26 and
this being simultaneously applied to the fluid in the compartment 35
of the cylinder 23 acts on the piston 25, so 70 that equal pressure is
maintained on the rams 5 and 6 and the pressure is equally distributed
throughout the length of the member 2 The working surfaces of the
members 1 and 2 will generally be adjusted to 75 the horizontal but it
will be understood that in accordance with the work to be carried out
these may be slightly inclined, and are adjustable for this purpose,
and the member 2 will maintain its adjustment throughout 80 its
working stroke The upper member I may be adjusted in any convenient
manner either bodily or one end relative to the other and the member 2
may be adjusted by opening the valve 38 so that the rams, 5, 6 can 85
be moved independently one of the other.
It is to be understood that the invention is not restricted to use in
upstroke presses but is equally applicable to downstroke or horizontal
stroke presses and to other metal 90 working machines such as cutting
or punching machines.
Various modifications may be made without departing from the scope of
the invention For example, the positions of the 95 main and auxiliary
systems may be interchanged, or the auxiliary cylinders may be located
alongside the main pistons or above the movable member and in the two
latter cases additional rams for the pistons of the 100 auxiliary
cylinders are provided.

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* GB785541 (A)
Description: GB785541 (A) ? 1957-10-30
A device for varying the effective length of control linkages of motor cars
PATENT SPECIFICATION
785,541 Date of Applicon and filing Complete Specification Nov 12,
1953.
No 31446/53.
Application made in Switzerad on Nov 12,1952.
Complete Specification Published Oct 30,1957.
Index at Acceptance: lass 80 ( 3), Z 9.
International Classification:-Fo 6 h COMPLETE SPECIFICATION
A device for varying the effective length of control linkages of motor
cars I, Ric HARD HALLER, of Swiss nationality, of Brauerstrasse 51,
Zurich, Switzerland, 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:-
The invention relates to a device for varying the effective length of
control linkages for operation of a control rod of a motor car
According to the invention a device for operating a control rod of a
motor car comprises a part of the linkage between an actuating member
and the control rod of the motor car, the effective length of which
may be varied to such an extent that the control rod actuated by the
member may be brought to an end position merely by variation of the

effective length of said device and means provided for varying the
effective length of the said device.
This device is chiefly intended for the working of the pump lever of
internal combustion engines for motor cars, in which upon braking the
motor brake the fuel supply is required to be instantaneously
completely stopped.
The device of variable length consists, advantageously, of two pairs
of links mounted opposite each other on two bearing members, one of
which members is secured to a tubular part and the other member is
secured on a movable rod mounted within the tubular part, in such
manner that when opening or folding the links of the pairs of links,
the rod within the tubular part is moved Advantageously these links
are disposed on the bearing members in such manner that the oppositely
disposed links of the two pairs of links may be folded to a position
slightly beyond the dead-centre position, that is to say into a
position in which they are substantially parallel Thus the two pairs
of links are moved into that position in which the oppositely disposed
links are comlPrice 3 s 6 d l pletely folded, thus forming a rigid
connection between the tubular part and the rod movable therein, until
the oppositely disposed links are opened by means of a Bowden cable to
change the length of the 50 tubular part and the rod within it.
The invention is diagrammatically illustrated by way of example in the
accompanying drawings, in which:
Figure 1 is a side elevation of the first 55 embodiment of
construction of a control linkage in the open position; Figure 2 shows
the construction illustrated in Figure 1 in the closed position;
Figure 3 is a plan view according to Figure 60 2; Figure 4 is a plan
view of the second embodiment of construction of the control linkage
of a motor car; Figure 5 is a side elevation of the control 65 rod
linkage of a motor car-internal combustion engine with motor braking,
the linkage acting on the lever of the fuel supply pump and shown when
the motor is working; Figure 6 is the control rod linkage accord 70
ing to Figure 5 when the engine is operating as a brake; Figure 7 is a
side elevation of another construction of a control rod linkage of a
motor car-internal combustion engine with motor 75 braking when the
engine is operative; Figure 8 is the control rod linkage according to
Figure 7 in the open position when the engine is operating as a brake.
The construction illustrated in Figures 1, 80 2 and 3 of the device
for varying the effective length of a control linkage of a motor car,
is provided with a tubular part 1 and a rod 2 which is axially movable
A bearing member 3 is secured to the tubular part 1 and a bear 85 ing
member 4 is rigidly secured to the rod 2.
The links 7 and 8 which are mounted on the bearing member 3 by means
of two oppositely disposed spindles 5 and 6 each comprise two parallel

plates interconnected 90 and stiffened by a distance bolt while the
two links 11 and 12 each of which also consists of two plates and an
interconnecting and reinforcing distance bolt are mounted in a similar
manner respectively on two spindles 9 and 10 of the bearing member 4
The other ends of the links 7 and 11 and 8 and 12 are linked together
by spindles 13 and 14 respectively On the spindle 13 is mounted a
clamp 15 with clamping screw 16, in which the sheath 17 of a Bowden
cable is clamped, the core 18 of which cable is mounted by means of a
clamping screw 20 on the spindle 14.
The device, the effective length L of which is variable, is thereby
formeci by the bearing members 3 and 4 and the links 7 and 11 and 8
and 12 respectively.
The device is adapted to be inserted into a part of a control rod
which when pressure is applied moves in the longitudinal direction, as
hereinafter described in more detail with reference to Figures 5 and
6.
The construction of a device according to the invention for the
operation of a control member of a motor car as illustrated in Figure
4 corresponds in its essential parts with the construction as
previously described.
A tubular part 1 ' has a rod 2 ' which is axiallv displaceable therein
A bearing member 3 ' is secured to the tubular part 1 ' and the
bearing member 4 ' is rigidly secured to one end of the ro'd 2 ' The
ends of the two links 71 and 81 are mounted on the spindles 5 ' and 6
' of the bearing member 3 ' which are disposed opposite each other,
while the ends of the two links 111 and 121 are mnounted in similar
manner on two spindles 9 ' and 101 of the bearing member 4 ' The other
ends of the links 71 and 111 and 81 and 121 respectively are flexibly
joined together by one of each s Dindles 131 and 141 respectively A
clamp 151 is mounted on the spindle 13 ' with clamping screw 16 ' in
which the sheath 17 ' of a Bowden cable is rigidly clamped, the core
181 of which is clamped by means of a clamping screw 201 on the
spindle 141 The rod 21 extends through the tubular part 11 and
projects therefrom The bearing member 31 is provided on one side with
a lug 21 in which the one end of a pull rod 22, laterally disposed of
the link 71, 81, 11 ' and 121 is inserted and held in position on this
lug by a nut 23 which is screwed on to the winding provided at one of
its ends Externally of the bearing member 41 the pull rod 22 is bent
in such manner that the extension 221 is coaxial to the rod 2 ' The
device, the effective length of which is variable, consists also of
the bearing parts 3 ' and 4 ' and the pairs of links formed by the
links 7 ' and 11 ' and 81 and 121 respectively.
The device is further adapted to be inserted into that part of a
control rod which upon being pulled moves in the longitudinal

direction as is hereinafter described with reference to Figures 7 and
8.
With reference to Figures 5 and 6, 25 is an injection pump of a Diesel
engine with centritugal governor, not shown in the drawings, while 26
is the control lever of the injection 70 pump 25 The control lever 26
may be swung oetween the adjustment stops 27 and 28, in such manner
that when the control lever 26 rests on the stop 27, the fuel supply
is completely stopped, while maximum tuel supply 75 is providei when
the control lever 26 is moved against the stop 28 A spring 29 urges
the control lever '6 against the stop 27 thus tending to stop the
supply of fuel to the injection pump The control lever 26 is con 80
nected by means of a connecting rod 30, 301 to a lever 32 pivotted at
31 on the chassis of the vehicle, which is in its turn connected to
the accelerating pedal 34 by means of a rod 33 Betw een the parts 30
and 301 of 85 the clutch red -is provided a device according to the
invention as described with reference to Figures 1 to 3, which is
mounted in such manner that the part 30 of the connecting red is
rigidly connected with the tubular part 90 1 and -he part 30 ' of the
said connecting rod with the rod 2 advantageously by welding.
As illustrated in Figures 2 and 5, the links 7 and 8, and 11 and 12
respectively, are fo'ded into the operative position, which is 95
slightly beyond the position in which they lie parallel to the red 2,
so that the spindles 13 and 14 rest on the rod 2 The links 7 and 8,
and 11 and 12 respectively are locked in this position and form a
rigid connection between 100 the tubular member 1 and the rod 2, which
are inserted between the parts 30 and 30 ' of the connecting rod The
connecting rod 30, 301 is thereby adjusted to the length necessary for
operation so that it is rendered 105 possible by operating the
accelerating pedal 34 through the connecting rod 33, the lever 32 and,
this connecting rod 30, 301 to force the control lever 26 of the
injection pump away from the stop 27 as far as the stop 28, 110
against the action of the spring 29 When the motor brake is made to
function, the fuel supply should be stopped instantaneously.
This is effected by operating the Bowden cable 17, 18 the result being
that the links 115 7 and 8, and 11 and 12 respectively are spread
apart as illustrated in Figures 1 and 6 This spreading apart of the
links 7 and 8, and 11 and 12 respectively effects a considerable
reduction in the effective length (Figure 1) of 120 the device which
is mounted between the part 30-and 301 of the control rods so that the
control lever 26 of the injection pump 25 may be returned to the stop
27 at any time, completely independent of the position of the 125
accelerating pedal 34 When the motor brake is again in the inoperative
position, the Bowden wire 17, 18 is actuated in the opposite direction
so that the links 7 and 8, and 11 and 12 respectively are again

folded, 130 whereupon the control lever 26 of the injection pump can
at once be moved again by means of the connecting rod 30, 301 The
Bowden wire is advantageously connected to 785,541 which the effective
length of which is variable, consists of two bearing members ( 3, 4,
and 31 and 41 respectively) and two pairs of connected links ( 7, 11,
and 8, 12 or 71, 11 ' 70 and 8 ', 121) disposed oppositely to each
other, whereby the one bearing member ( 3 or 3 ') is securely mounted
on a tubular part ( 1 or 11) and the other bearing part ( 4 or 41) on
an axially displaceable rod ( 2 or 2 ') in this 75 tubular part ( 1 or
1 '), so that by spreading apart or folding of the links ( 7, 11; 8,
12 or 71, 111; 81, 121) of the two pairs of links the rod ( 2 or 21)
in the tubular part ( 1 or 1 ') may be displaced for actuating the
control rod, 80 and wherein the means for spreading and folding of the
links ( 7, 11, 8, 12 or 71, 111, 81, 121) of the ivo pairs of links on
the spindles ( 13, 14 or 13 ', 141) engage the spindles connecting
each of the pairs of links 85
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* GB785542 (A)
Description: GB785542 (A) ? 1957-10-30
Manufacture of lids, bowls, tanks and like shapes
Manufacture or lads, Bowls, Tanks and like Shapes,
3:, ARTHUR GEOFFREY DEEMING, a British
Subject, of 30 Hillcrest Grove, Staveley,
Derbyshire, 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:
The invention relates to the manufacture of lids, bowls, tanks and
other articles made from fibre and material which is fluid for
application to the fibre and which is afterwards set solid.
The invention comprises a process of rnaking lids, bowls, tanks and
other articles wherein fibre in the form of roving is wound on itself
between walls of a former or mould to forte a predetermined shape of
body or a portion of body of the article to be made and wherein the
fibre is impregnated with liquid solid-setting epoxy or polyester
resin before or after winding on the former. The liquid may be a hot
setting polyester or a cold material set solid by an accelerator.
In order that the invention may be clearly understood and readily
carried into effect, reference may be had to the accompanying
drawings, on which:
Figure 1 illustrates a means fo impregnating fibre roving;
Figure 2 is a sectional elevation of a moulding former constructed
according to this invention;
Figure 3 is a sectional elevation of a moulding former for a hollow
article;
Figure 4 shows a hollow article formed of two parts;
Figure 5 illustrates, in section, a modified form of mould or former;
Figure 6 is a front view of the parts shown by Figure 7;
Figure 7 shows a frame for supporting radial roving;
Fipre 8 shows modified formations of roving forming the body of a
moulding; and
Figure 9 illustrates a further modified form of mould or former.
In one convenient arrangement (Figure 1) roving 1 passes from the
"cheese" 2 through a guide tube 3 having a funnel shaped entrance, and
under a pivoted guide 4 which can be turned on its pivot 5 into
position to lie under a bath of liquid polyester. The impregnated
roving after leaving the liquid passes between two squeegee rollers 6
to remove surplus liquid on its path to the rotating mould or former
7. The rollers may be braked so that a pull is given to the roving to
increase the winding tension. The roving may be of glass, wool, cotton
or other fibre.
In one example (Figure 2), the former is adapted to mould a dome
shaped lid, cap or the like by winding the impregnated fibre in a
shaped annular space 8 between two plates 9 mounted on a centre
spindle 10 and a number of such spaced apart plates 9 may be mounted
on a screw threaded spindle 10, so that a number of lids can be
simultaneously moulded, each mould receiving a separate roving. The
wound material is suitably compressed in the mould and conveniently,
the said centre spindle or bolt 10 is removed, whilst the former is on

a jig, and a smaller diameter bolt is inserted and the former plates
pressed together endwise thereon. In some constructions, the tension
of the winding is sufficient to give the required solidarity.
The former (Figure 3) may be constructed to shape a hollow member
having a cylindrical or other shaped wall 11 with a dome shaped end
12, the former comprising two dome shaped spaced apart plates 13 and
14 mounted on a centre tube 16, the inner and smaller plate 14 having
a cylindrical or other shaped extension 15 at the outer edge.
The two parts are connected by the centre tube 16 having nuts 16a
screwed thereon.
The impregnated roving is wound on the former between the plates and
along the cylindrical extension. Curing is effected with the former in
position, after which the former is removed. Two of the shapes may be
assembled together to form a closed hollow body, by arranging the two
shapes on a centre spindle passing through the two tubes 17 (Figure
4). The walls of the separate parts are first wound to a thickness
only (Figure 3) to be self-supporting and to form a base for tte extra
winding to the broken lines as shown in Figure 4 the increased wall
thickness joining the two parts together.
The unit is cured at the required temperature and the centre bar
withdrawn from the tubing 16 at each end. This unit can be used as a
buoyancy tank or a pressure vessel. Resin sold under the Registered
Trade Mark "Epicote" may be used to impregnate the roving.
Longitudinal threads may be wound in for increased strength where
necessary. The process may be used to manufacture articles in glass
fibre and resin from a flat disc to bowl shaped or hollow articles.
Two bowl shaped articles may be used for the manufacture of spheres
and ovoids, and the former may be shaped to mould a spigot and socket
joint a as shown in Figure 5.
By using square or rectangular section die or former 18 (Figure 9) and
a square plate 19 the technique may also be used for the production of
square or rectangular tanks or bodies. In this case, it is necessary
to provide straps or plates 20 to place around the end portion 21 of
the rectangular moulding after winding to pull into the square or
rectangular shape, and the remaining portion can be similarly shaped.
Metal plates for strengthening- or rivet holding purposes may be
inserted between two formers 9. In one particular application to a pit
prop lid, a square plate pressed to match the contour of the mould and
having, for instance, four holes drilled, one in each corner, is
incIuded in the former so that it lays in the winding on the inner
side of a formed lid and in a centre position. After forming the lid,
these four holes are extended by drilling through the resin glass mass
and the extended holes countersunk on the outer face. By this means
rivets can be inserted through the lid, the heads of which will be

held by the metal plate. It has been found practicable in some
applications to dispense with the metal insert, and in this case two
formers, such as 9, have bolt holes therein at a position in alignment
with those required in the completed article for receiving bolts or
rivets.
The roving is wound in the stated manner up to the holes and bolts are
inserted through the holes to lie across the winding.
The winding is then continued with the bolts in position until
complete. The centre spindle is then withdrawn and consolidation of
the parts carried out by tightening the four bolts, thus compressing
the glass roving and resin and completely filling the centre hole.
Excess resin is also expelled by this means. The advantage of this
technique is that the lid is very strong at the fixing holes as none
of the applied fibres have to be cut by drilling. This prevents the
fixing bolt or rivet head from pulling through the finished item when
in service.
In addition to the roving being wound or coiled on the former, roving
can be incorporated to run radially at right angles or across the
coils or winding and at one or both sides of the coils. As shown in
Figures 6 and 7, separate lengths of roving 26 passes around the
spindle 22 on which the former 23 is mounted and the ends of each
length are attached by adhesive resin to wires connecting arms 24 of a
frame 25 fixed to the former 23, so that radial strands 26 of roving
are arranged to extend outwards from the space between the spaced
apart parts of the former between which roving is coiled. When a
hollow article is being moulded, the end portions 27 of the radial
roving 26 can be carried over the side of the inner former 23a to be
incorporated in the coiled roving of the annular wall of the moulded
article as well as the bottom or end wall portion. The roving strands
may be sufficiently long to pass over and thus reinforce the rim of a
hollow article and can also be sufficient to extend across and to
strengthen the joint such as described with reference to Figure 4. By
arranging a number of spaced apart rows 28 of lengths of roving in the
mould and by coiling roving from a separate cheese between each row, a
structure similar to that shown by the lower half of Figure 8 is
obtained with coiled windings 28a between the said rows 28 of radial
or outwardly directed strands.
The individual cheeses of roving may be revolved around in a path
concentric with the centre spindle whilst the former itself remains
stationary. If a frame 25 is moved backwards and forwards to move the
strands 26 transversely across the space between walls of the mould,
the radial roving will lie in a zig-zag path as shown at 26a on the
upper half of Figure 8.
Generally, in the case of tanks and closed vessels it is not necessary

to fill the central hole through which the mounting spindle passes, as
a tube fitting may be an integral and necessary part of the final
vessel. When a tank or half vessel is complete, a locking nut 16a is
applied at each side of a tube 16 (Figure 3) after coating the screw
threads of the tube and the adhering faces of the lock ing nuts with
an adhesive such as epoxy resin (resins sold under Registered tirade
Marks "Epicote" and "Araldite" have been used for this application).
The tube 16 and locking nuts 16a may be of metal, coated or otherwise,
or of thermoplastic or reinforced resin. If the central hole is not
required, a threaded bolt is used as the mounting spindle, as this may
be screwed out of the cured part quite readily leaving a threaded hole
into which a plug of reinforced resin or thermosplastic, or even
metal, may be inserted.
Strength may be added to the walls of an article or vessel moulded as
aforedescribed by winding on strips of impregnated woven glass or
other cloth. Impregnated glass cloth may also be incorporated in the
final winding of the former and may be extended over the edges of the
vessel for strengthening purposes, roving being used to consolidate
this.
The liquid solid-setting material can be sprayed on the fibrous
material as it is being wound in the mould. This method is
particularly convenient with the so-called coldsetting resins, as the
accelerator is added to to the catalysed resin as it emerges from the
spray gun or is drawn into the main stream of resin at the gun nozzle
from a separate container. By this means the risk of setting or curing
in the spray gun container is obviated. The liquid solid-setting
material can be impregnated by vacuum in the fibrous material which is
preformed in a dry or semi-dry state and placed in a chamber from
which air is then evacuated to a low pressure. Resin is introduced
into the chamber and the pressure of the atmosphere or even greater
pressures may be applied on the resin which forces it into the
preformed winding.
It has previously been proposed to manufacture discs, washers, brake
linings or the like by winding upon a bobbin, between cheek-plates
mounted thereon, yarn (including rovings) or tape composed of cotton,
ramie, flax, silk, wool, asbestos or other suitable fibrous material,
impregnated with the phenolic formaldehyde condensation binding and
hardening agent, removing the discs so formed from the bobbin and
drying the same. A method has also been proposed to make endless
friction facings which comprises winding a strip of fabric treated
with a heat hardenable binder, and having previously shaped recessed
and projecting portions on opposite sides thereof and extending
longitudinally of the strip, in a body such that the projections of
the fabric nest with recesses of adjacent convolutions and subjecting

the body to pressure and heat to compact the convolutions thereof
into, a substantially rigid friction facing and to harden the binder.
What I claim is : -
1. A process of making lids, bowls, tanks and other articles wherein
fibre in the form of roving is wound on itself between walls of a
former or mould to form a predetermined shape of body or a portion of
a body of the article to be made and wherein the fibre is impregnated
with liquid solidsetting epoxy or polyester resin before or after
winding on the former.
2. A process of making lids, bowls, tanks and other articles as set
forth in
Claim 1, in which the walls of the mould are pressed towards one
another to compress the material moulded therebetween.
forth in Claim 1, in which one of the walls of the former or mould has
an annular wall extending therefrom on which the fibre is wound to
form a hollow body.
4. A process of making tanks and other hollow anicles as set forth in
Claim 1, in which two bodies after setting are joined together by
winding impregnated fibre roving or woven fabric over the joint and
allowing the added portion to set to form a solid wall joining the two
parts.
forth in any of the preceding claims, in which strands of fibre roving
or woven fabric are incorporated at right angles to or across the
winding or coils.
forth in any of the preceding claims, in which metal plates for
strengthening or rivet holding purposes are incorporated in the
moulded body during the moulding process.
forth in any of the preceding claims, in which bolt or like holes are
formed in the article during the winding process.
8. A lid, bowl, tank, container or other shaped article made according
to the process as set forth in any of the Claims 1 to 7.
9. A process of and means for making lids, bowls, tanks, or other
articles, substantially as herein set forth and illustrated in the
accompanying drawings.

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