вход по аккаунту


Патент USA US3099737

код для вставки
July 30, 1963
Filed Jan. 22, 1962
I nventor
United States Patent 0
Patented July 30, 1963
acteristics, such as 3 and 4, are mounted on contact mul
Svante Lennart Hjertstrand, Hagersten, Sweden, assignor
to International Standard Electric CorporationLNew
Yorlr, N.Y., a corporation of Delaware
Filed Jan. 22, 1962, Ser. No. 167,506
Claims priority, application Sweden Feb. 1, 1961
8 Claims. (Cl. 200-87)
tiple strip 2 and extend into close but noneabutting rela
tion with the multiple strip 1. Contact plugs 9 and 10,
shown in more detail in ‘FIGURE 3, are mounted on con
tact multiple strips 1 and ‘1x1 in similar relation but they
are not both secured to the same strips,
These contact
plugs serve as contact points when the intersecting mul
tiple strips are actuated.
Operating conductors 5, 6 ‘and 12. are associated with
This invention relates in general to crossbar switches 10 their respective multiple strips 1, .2 and 11 and are posi
tioned between the noted contact plugs. Thus, each con
and in particular to crossbar switches in which each con
tact multiple strip has its own operating conductor suit
tact set is selectively operable in response to the establish
ably secured‘thereto. The operating conductors may be
ment of a magnetic attraction between the intersecting
secured to their associated multiple strips in any suitable
horizontal and vertical rows of contact multiples. Its
principal object is to provide a new and improved cross 15 manner which permits the conductors to be electrically
insulated from the multiple strips.
bar switch of the above character which is simple yet re
‘In order to operate any contact set of the crossbar
liable in operation.
switch, simultaneous and cooperating currents are placed
Crossbar switches requiring a plurality of hold magnets
on the operating conductors associated with the horizontal
and select magnets are gradually being replaced by elec
tronic devices such as gas-gap tubes, transistors, and 20 and vertical contact strips which de?ne the contact set
to be operated. The noted currents suf?ciently magnetize
PNPN diodes, primarily as a result of expense and size
the operating conductors to cause their attraction toward
requirement of conventional crossbar switches. While
one another thereby bringing the two intersecting mul
these electronic devices have advantages in switching
tiple strips into electrical conductivity with each other
speeds, they are subject to disadvantages regarding their
reliability, economy, maintenance and transmission qual 25 through the associated contact plugs.
The current flowing through the selected operating con
ity. While the disadvantage of electronic components as
doctors is regulated so that electrical contact is established
to economy and reliability may be overcome, the trans
at a crosspoint only
both operating conductors are
mission qualities are not expected to match those of pre
energized. Thus, a contact set will not be operated if
cious metal pressure type contacts. One reason for this
is that the amount of crosstalk or attenuation depends on 30 only one operating conductor is energized. In this way
it is possible to select a connection between any hori
the contact resistance and the degree of isolation of one
zontal and any vertical contact multiple by energizing the
contact from another. Electronic circuitry can compen
corresponding operating conductors.
sate for the noted attenuation by ampli?cation but such
Any contact set operated may be retained in its oper
ampli?cation will increase the level of crosstalk and thus
rendering electronic components unsuitable ‘for many 35 ated condition when the energizing current is removed
from the operating conductors by the remanence in the
magnetic circuit. This magnetic circuit is composed of
According to the present invention, the foregoing dis
the two contact plugs and the portion of each multiple
advantages are overcome by providing an economical,
compact crossbar switch using precious metal contacts
strip lying between the plugs.
which are easily actuated with a minimum of travel.
An operated contact set may be released by energizing
either of the multiple strip with a current in the opposite
direction ‘from the operating current. As is well known,
the release current may be of substantially smaller mag
nitude than the operating current.
A feature concerned with the compactness of the inven
tive device resides in the elimination of the usual hold
and select magnets and associated hold and select bars.
Another feature resides in the arrangement wherein the
contacts are operated by magnetic attraction therebetween
at each contact stao‘kup without a separate energizing coil
In order to achieve as good contact properties and con
tact pressure as possible, the contact surfaces are covered
per stackup being required.
with precious metal, such as gold or rhodium in a thin
layer. In order to secure separation between the movable
Other objects and features of the invention will become
apparent and the invention will be best understood by
parts of a contact on releasing, the whole system may be
reference to the accompanying drawing comprising FIG 50 closed in oil or in any other liquid with insulating proper
ties and suitable surface tension.
URES l to 3 wherein:
{FIGURE -1 shows two sets of contacts together with a
By this method the movable parts in an operated con
portion of the well-known intersecting horizontal and ver
tact are subjected to a separating force, which is counter
tical contact multiples modi?ed according to the inven
acted by the remanence. ‘On releasing, the separating
55 force becomes e?ective when the remanence force is
FIGURE 2 shows one embodiment of the invention
eleminated by the described counteracting current in either
wherein the contact sets have contact points carried by an
of the selection conductors belonging to the contact in
insulating member secured to one of the contact multiples;
For selection applications some contacts can co-operate
FIGURE 3 shows another embodiment where the con 60 so that poles belonging to the same device in a system
tact points are carried by separate horizontal and vertical
Referring now to FIGURE 1 of the drawings, a de
scription of the invention will be given.
The switch section illustrated comprises a horizontal
contact multiple strip 1 and a pair of vertical contact
multiple strips 2 and 11. These multiple strips are made
of a ?exible magnetic material which has good electrical
operate simultaneously in a manner familiar, for example,
in crossbar systems. In such cases the selecting circuits
containing the selecting conductors such as 5 and 6 are
connected in series or in parallel in order to achieve
operation simultaneously. Thus, the contact system can
function as a selecting device ‘and a registering device in
conductivity. The multiple strips are arranged in hori
telecommunication systems. The operation of the selector
equipment is effected by currents in the selector conduc
zontal and vertical rows with the horizontal and vertical
tors, which are connected to one or more markers con
70 trolling the system, :and which by numerical and non
rows being located in adjacent parallel planes.
A pair of contact plugs of magnetic and electrical char
numerical selections and by methods whose principles
are known, investigate the possible devices in the selector
system which would be useful in the actual case‘.
FIGURE 2 shows a contact plug mounting arrange
ment wherein each of the plugs 3 and 4 are mounted on an
insulating strip 7 with neither of the contact plugs in
electrical contact with the associated contact multiple
strips 1 and 5. When the multiple strips are attracted
after de-energization of the associated operating conduc
3. A crossbar switch contact assembly as set forth in
claim 1 wherein said electrical connection is severed re
sponsive to the energization of one of the operating con
ductors associated with the energized magnetic circuit in
a direction opposite to the said ?rst energization.
to each other, the contact plugs establish electrical con
4. A crossbar switch contact assembly as set forth in
tact therebetween.
claim 1 wherein the said contact means are electrically
FIGURE 3 shows the contact plugs 9 and 10 electri 10 connected to the contact strips in one plane.
cally mounted on associated multiple strips. Plug 9 is
5. A crossbar switch contact assembly as set forth in
electrically connected to strip 11 and plug 10' is electrically
claim 1 wherein said contact means includes an insulating
connected to strip 1. The contact assembly can be con
member supporting contact elements space separated from
structed according to any of these arrangements.
the associated contact strips.
While the principles of the invention have been de 15
6. A crossbar switch contact assembly as set forth in
scribed above in connection with speci?c apparatus and
claim 1 wherein each said contact means includes a pair
applications, it is to be understood that this description
of contact elements and wherein each contact strip of
is made only by way of example and not as a limitation
any said magnetic circuit includes one of such pair of
on the scope of the invention.
contact elements electrically connected thereto.
I claim:
7. In a crossbar switch contact assembly as set forth in
1. A cross bar switch contact assembly comprising a
claim 1, support means for normally maintaining an air
plurality of ?exible contact strips of magnetic material
gap in said magnetic circuit between the associated con
arranged in parallel rows in ?rst and second parallel
tact strips and said contact means, the air gap being di
planes with the contact strips in one plane positioned
mensioned to preclude energization of said magnetic cir
normal to the strips in the other of said plane, contact 25 cuit by energization of only one of said contact strips.
means positioned between the contact strips of said planes
8. A crossbar switch contact assembly as set forth in
at each of the crossover points of the contact strips of
claim 1 ‘wherein de-energ-ization of the operating conduc
one plane with the contact strips of the other plane, each
tors associated with any energized magnetic circuit opens
of said contact means and adjacent portions of said con
the said electrical connection.
tact strips de?ning a separate magnetic circuit, and a
selectively energiz-able operating conductor extending
longitudinally of each of said contact strips ‘for generat
ing magnetic ?ux in the associated contact strip, the gen
eration of magnetic flux in any con-tact strip in both of
said planes energizing the said magnetic circuit at the
crossover point thereof to establish electrical connection
between the last said contact strips.
2. A crossbar switch contact assembly as set forth in
claim 1 wherein magnetic remanence in any said ener
gized magnetic circuit maintains said electrical connection 40
References Cited in the ?le of this patent
White _______________ __ June 10,
Levine et al ____________ __ Dec. 1,
P?eiderer _____________ __ Jan. 12,
Nitsch ________________ _. May 9,
La Tour _____________ __ Sept. 26,
P?eiderer ____________ __ Nov. 21, 1961
Без категории
Размер файла
316 Кб
Пожаловаться на содержимое документа