RELAIS ELECTROMAGNETIQUE

ELECTROMAGNETIC RELAY

Abrégé anglais

Abstract of the Disclosure
Electromagnetic Relay
The invention relates to an electromagnetic relay in which
the magnet yoke (18), with the aid of lateral projections
(28, 29) is positionally fixed in cut out portions (26, 27)
provided in the side walls of a housing member. When looked
at in the longitudinal direction (25) two cut out portions
(26, 27) are provided for behind each other, in each of
which there is a supporting web (31, 32). The one of these
cut out portions (26), together with the supporting web (31),
serves as the swivel point for the magnetic system and the
other one of the cut out portions (27), together with its
supporting web (32) is positioned in such a way that the mag-
netic system is in such an installation position that, in
the state of rest of the armature (19), the contacts (11, 12,
13, 14) are in the operative position. By deforming the
cut out portion (27) owing to a bulging of the cover portion
(5) and the supporting web (32), the magnetic system is
pressed in the downward direction and, in the course of this,
swivelled about the supporting point (33). Upon or after
reaching the switchover point of the contacts (11, 12, 13,
14),the adjusted position is assumed and the further de-
formation is stopped. In this way it is possible to achieve
a simple adjustment of the magnetic system (15) relative to
the contact system (8).
(Fig.1)

Revendications

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THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An electromagnetic relay comprising a housing made of
a deformable plastics material having a cover and a plurality of
sidewalls one of which has at least one cut-out into which first
and second spaced laterally projecting portions of a magnet yoke
extend, the cover forming an upper closure of the cut-out, a
tilting armature having means for operating a contact set and
being urged into engagement with the yoke adjacent the second
laterally projecting portion by spring means, the first lateral
projecting portion resting on a first housing sidewall portion
which projects upwardly into the cut-out and the second lateral
projecting portion being secured between a second housing sidewall
portion which projects upwardly into the cut-out and a portion of
the cover which has been deformed downwardly to an extend neces-
sary to adjust the contact set to the proper operating position
by swivelling of the yoke about the first housing sidewall portion,
such downward deformation being accommodated by consequent defor-
mation of the second sidewall portion.
2. A relay as claimed in claim 1, in which the armature
is generally L shaped, comprising two legs one of which overlies
the yoke and the other of which projects downwardly over an end
of the yoke.
3. A relay as claimed in claim 2, in which the contact
set is located above the yoke and includes a contact spring hav-

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ing a fixed end and having a free end engageable with cam
means on the armature for movement of the contact spring into alter-
native engagement with two fixed contacts, the first housing
sidewall portion being located between the fixed end and the
fixed contacts, and the second housing sidewall portion being
located between the fixed contacts and a point of engagement
between the yoke and armature.
4. A relay as claimed in claim 3 in which the spring means
is integrally formed with a coilform of the relay.
5. A relay as claimed in claim 1, 2 or 3 in which there
are two cut-outs respectively accommodating the first and second
laterally projecting portions.
6. A method of making the relay of claim 1 comprising
initially assembling the relay components including the yoke,
armature, contact set, means for operating the contact set and
spring means into the housing with the second lateral projecting
portion initially resting on the undeformed second sidewall por-
tion and carrying out a subsequent adjustment step which involves
simultaneously measuring the contact spacing of the contact set
while deforming downwardly the portion of the cover overlying the
second sidewall portion and simultaneously deforming downwardly
the second sidewall portion, thereby swivelling the yoke about
the first sidewall portion until the desired contact spacing
is reached after which the deformation is stopped.

Description

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The present invention relates to an electromagnetic relay, with
a housing whose side walls consist of plastics material and have
cut out portions into which the magnet yoke extends with its
lateral edge without any backlash, and is thus in a fixed post-
lion in the assembled state of the magnetic system.
A relay of this type is known, for example, from the German Patent
No. 22 13 146 which issued on October 14, 1982 in the name Werner
Minks and the German Utility Model No. 78 28 023 which is dated
May 8, 1980 and is in the name Standard Electric Lawrence AGO In
the latter, laterally projecting flaps are provided for on the
magnet yoke which, during the assembly, each engage into a cutout
provided for in a sidewall. The contact systems, following the
installation of the magnetic system, must be adjusted in accordance
with the position of installation of the magnetic system. Owing
to the elasticity of the employed contact materials, this is a
relatively complicated and long-lasting procedure.
It is the object of the present invention to design a relay of the
aforementioned type in such a way that the adjustment of the con-
tact system relative to the magnetic system or the armature actual-
in the contact system, can be carried out in a quick and uncompli-
acted manner.
According to one aspect, the invention provides an electromagnetic
relay comprising a housing made of a deformable plastics material
having a cover and a plurality of sidewalls one of which has at
least one cut-out into which first and second spaced laterally
~r4 it

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projecting portions of a magnet yoke extend, the cover forming
an upper closure of the cut-out, a tilting armature having means
for operating a contact set and being urged into engagement with
the yoke adjacent the second laterally projecting portion by
spring means, the first lateral projecting portion resting on a
first housing sidewall portion which projects upwardly into the
cut-out and the second lateral projecting portion being secured
between a second housing sidewall portion which projects upwardly
into the cut-out and a portion of the cover which has been dolor-
mod downwardly to an extent necessary to adjust the contact swept the proper operating position by swiveling of the yoke about
the first housing sidewall portion, such downward deformation
being accommodated by consequent deformation of the second side-
wall portion.
According to another aspect, the invention is a method of making
the relay of the immediately preceding paragraph comprising
initially assembling the relay components including the yoke,
armature, contact set, means for operating the contact set and
spring means into the housing with the second lateral projecting
portion initially resting on the undeformed second sidewall port
lion and carrying out a subsequent adjustment step which involves
simultaneously measuring the contact spacing of the contact set
while deforming downwardly the portion of the craver overlying the
second sidewall portion and simultaneously deforming downwardly
the second sidewall portion, thereby swiveling the yoke about
the first sidewall portion until the desired contact spacing is
reached after which the deformation is stopped.

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The invention will be described in greater detail with reference
to the accompanying drawings, in which:

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Winks 32
Fugue is a sectional side view of a relay
Fugue, on a reduced scale, shows part of a top vie,
without the cover of the housing, Partly
i sectionally,
Fugue, on an enlarged scale, shows part of the one
cut out portion prior to the adjustment, in a
side view, and
Fugue shows the same part as Fugue, after the adjust-
mint.
The reference numeral 1 indicates a shell-shaped housing
member of thermoplastic material with plug holes pa and plug
pins Zb, a sidewall 3, a bottom me~ber4, a cover portion 5
and a front part 6. The terminal elements 7 are mounded into
the sidewall 3, with these elements extending to the contact
system 8 as projecting on the top consisting of a contact
terminal 9, a contact spring 10 welded thereto, and the
movable contact elements 11, 12 attached thereto, which co-
operate with the fixed contact elements 13 or 14 respectively.
One terminal element 7 is connected to the not shown coil
of a magnetic system 15 which still consists of the coil form
16, a coil core 17, a magnet yoke 18 connected to -the coil
core 17 and of a movable armature 19 which, in the example, is
designed as a tilting armature. The latter, with the aid of
a pressure spring 20, is pressed against the end edge 21 of
the magnet yoke 18 and is thus slew ably supported. The
pressure spring 20 may be attached to the coilfo~m or else
mounded thereto, so as to form one structural unit therewith.
In the state of rest, the one leg 22 of the armature 19 rests
on the magnet yoke 18. A plastics switching cam 23 attached
to the armature I is capable of actuating the end 24 of the
contact spring 10.

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Winks 3Z
Two such shell-shaped housing members 1 form one housing
part inside which the magnetic system 15 it fixed in position.
This housing may also consist of several parts, for
example as shown and described in the German Utility Model
No. 78 28 023~ According to the invention, in the side
wall 3, as seen in the direction of the longitudinal axis
25, two cut out portions 26 and 27 are provided for at a
spaced relation. These cut out portions are engaged by a
lateral projection 28 en 29 of the magnet yoke 18 without
any backlash. The lower surface 30 of the cut out portions
26, 27 is provided with supporting webs 31 and 32 on which
the projection 28 or I rests The supporting point of the
` cut out portion 26 as provided for and shown on the left
in Fugue, serves as the swivel point 33 for the magnet yoke 18.
For adjusting the magnetic system 15 with respect to the con-
tact system 8, the magnet yoke 18 can be lowered in the cut
out portion 27, in such a way that a pressure is exerted from
above with the aid of a hot and/or ultrasonic energized
stamp upon the cover portion 5, thus causing the supporting
web 32 of the cut out portion 27 to become softened and up-
set in the downward direction. This process is carried out
by simultaneously measuring the contact spacing at the
switching cam 23 engaging at the end 24 of the contact
sprung 10, for example, by measuring the switching point while a
voltage it applied to the contact system 8. Following the
exact adjustment especially during or after the switching
from the one into the other switching state, the stamp pros-
sure is either removed or the stamp is completely lifted off,
so that the magnetic system 15 will remain in the adjusted
position owing to the cooled down and solidified, deformed
supporting web 32, and is firmly retained in position also
by the part 34 of the cover portion 5 which, at this point, is

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Winks 37
likewise pulled through towards below, and has cooled
down and solidified (Fugue).
Preferably, the cut out portion 27 with the supporting
web 32 to be deformed, is provided for in the area of the
end edge I of the magnet yoke 18~ which serves as the
swivel axis, and the projections2q are likewise provided
for at the end of the magnet yoke 18.
According to the invention, it is actually also possible,
instead of providing two cut out portions 26, 27~ to combine
them to form one single cut out portion practically extend
in throughout the length of the magnet yoke 18~ In this
case, the entire lateral edge of the magnet yoke 18 could
be lying in the cut out portion. Also, the supporting web
31 may be formed by correspondingly shaping the magnet yoke
18, with the swivel point being fixed in this way.
it is still to be noted that it is necessary for the support-
in web 33 and the cut out portion 27 to be disposed in such
a way that in the original, hence in the non-deformed state,
the magnet yoke 18 and, consequently, the entire magnetic
system 15 will come to lie too high, and that the other pair
of contacts 11, 12 is closed. Owing to the deformation of the
supporting web 32 and the part 34 of the cover portion 5, the
pair of contacts 11, 13 is opened, and the lower pair of con-
teats 12, 14, is closed. This criterion preferably serves as
an indicating and setting condition for the adjustment.
The relay Jay also be closed by a lid and, if so required, can
be made wash tight by taking suitable steps, such as sealing.