POMPE A ARMATURE OSCILLANTE POUR AQUARIUM ALIMENTEE EN COURANT ALTERNATIF

A.C. OPERATED OSCILLATING ARMATURE AQUARIUM PUMP

Abrégé anglais

ABSTRACT
An oscillating armature pump for liquids operated
by alternating current and having a housing defining a
pump cavity, with a. c. coils mounted laterally of the
cavity on a block. The oscillating armature is mounted
on a plate spring which is secured to the pump housing,
and the armature is also provided with a resiliently
flexible plate for executing the pumping movement. The
plate spring is substantially U- or Omega-shaped, so
that it takes up a minimum space, and also provides a
favorable transition between the active oscillating end
of the spring plate and the static end of the plate se-
cured to the housing.

Revendications

The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:
1. An oscillating armature pump operated by alter-
nating current, especially a circulating pump for aquariums,
which comprises:
a housing which defines a pump cavity;
a substantially U-shaped plate spring, one end of which
is secured to said housing and at least the other free end of
which projects at least partially into said cavity;
an armature, one side of which is mounted to said other
free end of said plate spring and is located in said cavity;
and
a resiliently flexible thin plate which is secured to
one side of said armature remote from that side thereof
mounted to said plate spring, and which, for executing a
pumping movement, is adapted to be reciprocated in the
manner of a fishtail.
2. A pump according to claim 1, in which said plate
spring is substantially omega-shaped.
3. A pump according to claim 1, in which said plate
spring is substantially shaped in the manner of a fishhook.
4. A pump according to claim 1, in which at least
said ends of said plate spring extend at least substantially
at right angles to one another.
5. A pump according to claim 1, in which one end of
said plate spring is secured to the rear end face of said
pump housing and extends substantially at right angles to

the longitudinal extension of said thin plate when the latter
is in a rest position.
6. A pump according to claim 1, in which said plate
spring projects arcuately beyond the pump housing on that
side thereof remote from that side of said armature to
which said thin plate is secured.
7. A pump according to claim 1, in which said pump
cavity is closed by a yoke which encloses said plate spring
and is located on that side of said housing remote from
that side of said armature to which said thin plate is se-
cured.
8. A pump according to claim 7, in which one end of
said yoke and one end of said plate spring are mutually
secured to said pump housing.
9. A pump according to claim 1, in which said re-
siliently flexible thin plate is made of a material selected
from the group consisting of rubber and rubber-like plastics
material.

Description

~2~
OSCILLATING ARMATURE PU~P
The present invention relates to an oscillating arma-
ture pump opera~ed by alternating current, especially a cir-
culating pump for aquariums, in which the armature is secured
to a plate spring and is provided with a thin plate which is
made o rubber or rubber-like plastics material and which,
for carrying out the pumping movement, is reciprocatable in
the manner of a fishtail.
In kno~n pumps of this kind, an elongate plate spring is
provided in the form of a flat plate which is rigidly clamped
at one end and a~ its free end supports the armature. Since
with these springs a high specific continuous loadability is
required, a predetermined minimum cross-sectional dimension
is required. As a rssult of this, however, the rigidity of
the spring can be vbtained only by varying the leng~h of the
spring if the amplitude of the armature 7 and hence that Qf
the plate, is to be increased. Such a step, however, ca~ses
difficulties in small pumps.
The obJect of the in~ention is based on increasing the
active length of the plate spring without having to sub~
stantlally modify the dimensions of ~he pump housing. At
the same time~ it is an aim to obtain a simpli~ied clamping
of the plate spring on khe pump hsusîng.
These and other objects and advantages of the present
invention will appear more clearly from ths following speci-
fication in conne~ion with the accompanying drawing~ in
'~b

which:
Figure l shows a plan view of a circulating pump fo~
aquariums; and
Figure 2 shows a section taken on the line II-II of
Figure l.
In accordance with the present invention there is pro-
vided an oscillating ar~ature pump operated by alternating
current, especially a circulating pump for aquariums, which
comprises a housing which defines a pump ~avity; a substan-
tially U~shaped plate spring~ one end of which is secured
to said housing and at least the other free end of which
projects at least partially intn said cavity; an armature~
~ne side of which is mounted to said other free end of said
plate spring and is located in said cavity; and a resilien~ly
flexible thin plate which is secured to one side o~ said
armature remote from that side thereof mounted to sald plate
spring, and which~ for executing a pumping movement, is
adapted ~o ~e recipro~ated in the manner o a f1-h~ail.
The legs or shanks of ~he plate spring may bP parallel
to one another, or they may diverge~ Thus, it is also
possible to provide a fishhook shape or omega~shape.
In these embodiments?one end of the plate spring is
conn~cted to the pump hQusing~ and the other end is con-
ne~ted to ~he arma~ure9 which in a known manner may be pro-
duced by clamping, screwîng thereon, or ~he like. For ~he
purpose of i~proved securing7 th~ shanks may also be pro-
vided with small bends, if or securing reasons th~s leads
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, . . . . .

to a simpli~ication~
Referring now to the drawing in detail, the pump hous-
ing is a plastics or synthetic material body having a pump
cavity 1 deined by a rigid base plate 2 and by side blocks
3, which are used ~o receive9 preferably molded-in, alter-
nating curxent coils (not shown in detail). At the front
end of the pump cavity 1 is the outlet 4 at the end of a
taper or constriction 5. The pump housing is open at its
upper side.
Between the two blocks 3, or the alternating current
coils located there~ an armature 6 is arranged which is
secured to a pla~e spring 7 of steel or the like, and at
its front end the armature s~pports a thin ru~ber plate 8
This rubber plate 8 is rec~procaked in the manner of
a fishtail, in acGordance with the double arrow 9, in order
so ~o draw in aquarium wa~er via the ope~ top side o~ the
pump h~using and to eject it through the outlet 4 ~see
arrows 10). It ~s, however~ also possible or a portion o
the inflow to occur also via the rear end of ~he pump
cavity 1.
The plate spring 7 ls curved or arcuate, and in par~ic-
ular substantially U-shaped, with one end 11 of one shank 12
secu~ed to the axmature 6~ ~nd one end 13 of the ather shank
14 secured to one of the bloc~s 3. While the end 11 is re-
tained by clamping in a slo~ in.the armature 6, the end 13 is
preferably secured ~o the block 3 by screwing or riveting.
~e rear end of the p~mp ca~ity 1 may also be provided with
- 3 -

9~s
a yoke 15, the ends of which are also connPcted to theblocks 3, to provide a rear closure of the pump cavity 1.
The pre-shaped plate spring 7 not only permits a pre-
deter~in~d spring characteristic in the narrowest space to
be obtained, but moreover9 from a strength point of view,
provides a favorable transition between the active, oscil-
lating part of the plate spring 7, and the securing point
or the part of the plate spring 7 (end 13) which is con-
stantly at rest. Thus, a substantial increase of the service
life of the dynamically highly-stressed plate spring 7 is
attained. Furthermore, the mounting of the clamped-in plate
spring end is simplified; the end 13 can be screwed directly ~ -
to the rear end face of one of the blocks 3. The described
shaping o the plate spring 7 provides end portions of this
spring (ends 11, 13) which assume right angles relative to
: one another.
The present invention ~s, of course, in no way re-
stricted to the speci~ic disclosure of the spe~iflcation
and drawing, but also encompasses an~ modi~ications with~
in the scope of the appended clalmsr
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