U.S. patent application number 10/900290 was filed with the patent office on 2005-02-03 for electromagnetic pump with oscillating core.
This patent application is currently assigned to INVENSYS CONTROLS ITALY Srl. Invention is credited to Buffet, Jean Claude.
Application Number | 20050025638 10/900290 |
Document ID | / |
Family ID | 33524073 |
Filed Date | 2005-02-03 |
United States Patent
Application |
20050025638 |
Kind Code |
A1 |
Buffet, Jean Claude |
February 3, 2005 |
Electromagnetic pump with oscillating core
Abstract
Electromagnetic pump with oscillating core, connected to a
hydraulic device, to transfer a fluid into the hydraulic device.
The pump includes a containing body, a tubular element of amagnetic
material, a core of ferromagnetic material sliding coaxially to the
tubular element, an electromagnetic unit arranged around the core
and coaxial to the tubular element to generate an alternating
magnetic field and cause the core to slide axially and alternately
with respect to the tubular element. The tubular element includes,
in one piece, a first part, projecting outside both the containing
body and the electromagnetic unit and having an attachment
configured to be selectively associated, directly or indirectly,
with mating attachment elements of the hydraulic device, and a
second part disposed inside both the containing body and the
electromagnetic unit and having an axial cavity in which the core
slides. The tubular element further includes, in one piece, a
flange between the first part and the second part and configured to
allow the direct mounting of the tubular element to the containing
body and the electromagnetic unit.
Inventors: |
Buffet, Jean Claude;
(Sospel, FR) |
Correspondence
Address: |
STEVENS DAVIS MILLER & MOSHER, LLP
1615 L STREET, NW
SUITE 850
WASHINGTON
DC
20036
US
|
Assignee: |
INVENSYS CONTROLS ITALY Srl
Belluno
IT
|
Family ID: |
33524073 |
Appl. No.: |
10/900290 |
Filed: |
July 28, 2004 |
Current U.S.
Class: |
417/416 ;
417/417 |
Current CPC
Class: |
F04B 17/046
20130101 |
Class at
Publication: |
417/416 ;
417/417 |
International
Class: |
F04B 017/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 30, 2003 |
IT |
UD2003A000162 |
Claims
1. Electromagnetic pump with oscillating core able to be connected
to a hydraulic device to transfer a fluid at a determinate pressure
into said hydraulic device, comprising: a containing body, a
tubular element made of amagnetic material, a core made of
ferromagnetic material able to slide coaxially to said tubular
element, an electromagnetic unit arranged around said core and
coaxial to said tubular element to generate an alternating magnetic
field and cause said core to slide axially and alternately with
respect to said tubular element, wherein said tubular element
comprises, in one piece, a first part, protruding outside both said
containing body and said electromagnetic unit and provided with
attachment means configured to be selectively associated, directly
or indirectly, with mating attachment elements of said hydraulic
device, and a second part disposed inside both said containing body
and said electromagnetic unit and having an axial cavity in which
said core is able to slide, said tubular element further
comprising, in one piece, a flange intermediate between the first
part and the second part and configured to allow the direct
mounting of the tubular element to the containing body and to the
electromagnetic unit.
2. Electromagnetic pump as in claim 1, wherein said attachment
means of said first part comprise a cylindrical, smooth and
non-threaded segment on a rear part of which a groove is provided
for the fast snap attachment to mating means of the hydraulic
devices.
3. Electromagnetic pump as in claim 2, wherein an adaptor element,
configured so as to be coupled with said attachment elements of
said hydraulic device, is able to be coupled with said smooth
segment and with the groove of said first part of said tubular
element.
4. Electromagnetic pump as in claim 3, wherein said connector
comprises an internal profile for its coupling with the external
profile of said smooth segment and with the groove of said first
part of said tubular element, and an external profile by means of
which it is able to be fast coupled with said hydraulic device.
5. Electromagnetic pump as in claim 3, wherein selectively
removable clamping means are provided to maintain said connector
associated with said first part of said tubular element.
6. Electromagnetic pump as in claim 5, wherein said clamping means
comprise an elastic element able to cooperate with said groove,
said groove being a circumferential groove.
7. Electromagnetic pump as in claim 5, wherein said clamping means
comprise a bayonet joint.
8. Electromagnetic pump as in claim 1, wherein said electromagnetic
unit comprises an electric coil arranged around said second part of
said tubular element, a ferromagnetic structure arranged around
said electric coil and an external insulating layer.
9. Electromagnetic pump as in claim 1, wherein said electromagnetic
unit is constantly held against said first circular flange by a
rear closing ring-nut, coupled with said second part of said
tubular element.
10. Electromagnetic pump as in claim 9, wherein said rear ring-nut
comprises a substantially tubular part coaxial to said tubular
element, and a second circular flange substantially parallel to
said first circular flange.
11. Electromagnetic pump as in claim 10, wherein said tubular part
of said rear ring-nut is provided with a through hole and with an
external surface connecting it with an external element, to allow
the entrance of said fluid inside said tubular element.
12. Electromagnetic pump as in claim 11, wherein said tubular part
also has an internal thread made in a zone close to said second
circular flange, able to allow said rear ring-nut to be screwed to
said second part of said tubular element.
13. Electromagnetic pump as in claim 12, wherein an elastic element
is arranged inside said second part of said tubular element between
said ring-nut and said core to constantly thrust said core towards
said first part of said tubular element.
14. Electromagnetic pump as in claim 1, wherein at least a shutter
is housed inside said first part of said tubular element,
constantly thrust towards said core by a spring arranged between
said shutter and an internal shoulder made in one piece on said
first part of said tubular element.
15. Electromagnetic pump as in claim 1, wherein said tubular
element is internally divided into two coaxial cylindrical
cavities, respectively a first high-pressure cavity, substantially
made in correspondence with said first part, and a second
low-pressure cavity, substantially made in correspondence with said
second part and inside which said ferromagnetic core is able to
slide.
16. Electromagnetic pump as in claim 15, wherein a bushing is
inserted into said tubular element to separate said two coaxial
cavities.
17. Electromagnetic pump as in claim 16, wherein a sealing ring and
a first elastic ring are interposed between said bushing and said
first cavity.
18. Electromagnetic pump as in claim 16, wherein a second elastic
ring is interposed between said bushing and said second cavity,
with the function of an end-of-travel element for said
ferromagnetic core and of absorbing the noise due to the action of
said ferromagnetic core itself.
19. Electromagnetic pump as in claim 1, wherein the hydraulic
device is selected from the group consisting of a boiler and an
electro-valve.
Description
FIELD OF THE INVENTION
[0001] The present invention refers to an electromagnetic pump with
oscillating core, that is, of the type comprising an
electromagnetic circuit with a core that is able to slide axially
and alternately inside a cylindrical seating in order to thrust, a
fluid, for example water, towards the exit with a desired pressure.
The pump according to the present invention is able to be
associated with hydraulic devices such as boilers, electro-valves
or other, and comprises a tubular element provided, on the side
through which the fluid exits, with rapid attachment means by means
of which the pump is able to be coupled with the relative hydraulic
device and, on the other side, with the cylindrical seating wherein
the core of the electromagnetic circuit is able to slide.
BACKGROUND OF THE INVENTION
[0002] Electromagnetic pumps with an oscillating core are known
(see, e.g., DE 299 19 575 U1 and DE 15 28 566 B); they generally
comprise a tubular element, wherein a cylindrical core made of
ferromagnetic material is able to slide, and a fluid to be brought
under pressure is able to pass. An electric coil is arranged around
the tubular element able to be fed with alternating current, in
order to generate an alternating, or pulsating, magnetic field with
the same frequency as the alternating current fed (for example 50
or 60 Hz).
[0003] Such pumps with an oscillating core are normally used in
small household appliances, such as for example ironing
apparatuses, coffee machines, steam vacuum cleaners or other, which
need small pumps in order to transport a fluid, for example from a
water tank to a boiler.
[0004] The alternate movement of the ferromagnetic core causes a
selective opening, or closing, of a pair of spring-type shutters,
which create a determinate pressure on the fluid exiting the
pump.
[0005] Usually the tubular element is connected to an external
terminal shaped in order to be coupled, with precision, to a
specific and well defined attachment profile of a hydraulic device
of the household appliance, arranged downstream of the pump, be it
an electro-valve, the terminal of a pipe of a boiler, or other. The
above-mentioned external terminal normally has the end threaded or
provided with a rubber-bearing profile. One example of such kind of
pump is disclosed in EP-A-288.216, on which is based the preamble
of the main claim.
[0006] In this way, however, each pump with a determinate external
coupling terminal can only be coupled to those hydraulic devices
that have a mating coupling profile, while in order to be connected
to different hydraulic devices it is necessary to resort to the use
of suitable adaptors which have to be placed between the pump and
the latter, with a consequent rise in the production and storage
costs of the spare parts.
[0007] Furthermore, in known pumps, sealing and end-of-travel rings
are arranged between the tubular element and the external terminal;
such rings separate the low-pressure cavity made inside the tubular
element and inside which the ferromagnetic core is able to slide,
from the high-pressure one, made in the external cavity and where
the spring-type shutters are arranged. Such sealing and
end-of-travel rings are inserted during the assembly phase of the
pump, making this operation complex and costly.
[0008] One purpose of the present invention is to achieve an
electromagnetic pump with oscillating core which can be installed
in a plurality of electric apparatuses, without needing to adapt
the hydraulic devices that constitute said apparatuses, according
to the profile of the external terminal of the pump itself.
[0009] A further purpose of the present invention is to optimize
the electromagnetic circuit of the pump, so that there are no
exposed metal parts, so that the pump is completely insulated
electrically.
[0010] Another purpose of the present invention is to achieve an
electromagnetic pump where the elements that constitute it are
reduced to the minimum and easily coupled to one another, in order
to reduce production times.
[0011] The Applicant has devised, tested and embodied the present
invention in order to overcome the shortcomings of the state of the
art, and to obtain these and other purposes and advantages.
SUMMARY OF THE INVENTION
[0012] The present invention is set forth and characterized in the
main claim, while the dependent claims describe other
characteristics of the invention or variations to the main
inventive idea.
[0013] In accordance with the above purposes, the electromagnetic
pump with oscillating core according to the present invention,
which is able to be connected to a hydraulic device such as a
boiler, an electro-valve or other, in order to transfer a fluid at
a determinate pressure into the hydraulic device, essentially
comprises a containing body, a tubular element made of amagnetic
material placed inside the containing body, a core made of
ferromagnetic material able to slide coaxially and internally to
the tubular element, and an electromagnetic unit arranged around
the core, external and coaxial to the tubular element in order to
generate an alternating magnetic field and cause the core to slide
axially and alternately with respect to the tubular element.
[0014] According to a characteristic feature of the present
invention, said tubular element comprises, in one piece, a first
part, protruding outside the containing body and the
electromagnetic unit, which defines itself fast attachment means,
without threading, able to be selectively associated, directly or
indirectly, with mating attachment elements of said hydraulic
device, and a second part inside the containing body and the
electromagnetic unit, in which the aforesaid core is able to
slide.
[0015] As an option, an adaptor element, consisting for example of
a fast tubular connector, which is shaped so as to be coupled to
said attachment elements of the hydraulic device, is able to be
coupled to the first part of said tubular element.
[0016] According to a further feature of the invention, the tubular
element comprises in one piece a flange provided in an intermediate
position between the first external part and the second internal
part. The flange allows to directly mount the tubular element on a
wall of the containing body without needing any auxiliary ring or
seal.
[0017] The tubular element is internally divided into two coaxial
cylindrical cavities: a first high-pressure cavity made
substantially in correspondence with said first external part, and
a second low-pressure cavity, with a diameter larger than the first
cavity, made substantially in correspondence with said second
internal part and in which the ferromagnetic core is able to
slide.
[0018] In the step where the pump is pre-assembled, a metal
bushing, for example made of brass, is inserted inside the tubular
element in order to separate the two coaxial cavities. Furthermore,
a sealing ring and a first elastic ring are placed between the
bushing and the first cavity, while a second elastic ring, which
acts both as an end-of-travel element for the ferromagnetic core,
and also as an absorber for the noise produced by the action of the
latter, is placed between the bushing and the second cavity.
[0019] The core made of ferromagnetic material is connected to at
least one spring-type shutter, arranged in the high-pressure
cavity.
[0020] In this way, all the elements that in the state of the art
were assembled individually and closed between the central element
and the external terminal are advantageously pre-assembled into a
single piece (the tubular element), which is the same for every
pump, irrespective of the different hydraulic devices to be
arranged downstream.
[0021] The electromagnetic unit, in turn, comprises an electric
coil, able to be fed with alternating current, in order to generate
a pulsating magnetic field, and cause the core to slide axially and
alternately inside the tubular element and, consequently, determine
the opening, or the closing, of the shutter.
[0022] The pump according to the present invention also comprises
clamping means, of the removable type, in order to keep the
connector associated to the tubular element. Such clamping means
can comprise, for example, an elastic clip, a tooth, a bayonet
joint, or other.
[0023] According to another characteristic feature of the present
invention, the electric coil and the other ferromagnetic parts of
the pump are completely covered and electrically insulated with
parts made of plastic material, in order to optimize the
electromagnetic circuit of the pump and hence the functioning
thereof.
[0024] In accordance with a further characteristic feature of the
present invention, said second part of the tubular element is
through inside the electromagnetic unit and is coupled,
advantageously by screwing, with a terminal element arranged on the
opposite side.
[0025] The tubular element and the terminal element are provided
with flange means, which enclose the electromagnetic unit and
define a structure that is very easy to assemble and, possibly, to
dis-assemble.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] These and other characteristics of the present invention
will become clear from the following description of a preferential
form of embodiment, given as a non-restrictive example, with
reference to the attached drawings wherein:
[0027] FIG. 1 shows an exploded view of an electromagnetic pump
with oscillating core according to the present invention;
[0028] FIG. 2 is a longitudinal section of the pump in FIG. 1 in an
assembled condition, including the optional connector;
[0029] FIG. 3 is an enlarged detail of FIG. 2.
DETAILED DESCRIPTION OF A PREFERENTIAL FORM OF EMBODIMENT
[0030] With reference to FIGS. 1 and 2, an electromagnetic pump 10
according to the present invention is of the type with an
oscillating core and is able to be connected to any hydraulic
device (electro-valve, boiler or suchlike) of a small household
appliance, of a known type and not shown in the drawings, such as
for example an ironing device, a coffee machine or other similar
electric apparatus, where there is the need to transport a fluid
under pressure, for example from a tank to a boiler.
[0031] The pump 10 according to the present invention
comprises:
[0032] a containing body 34,
[0033] a central element 11 comprising, in one piece and co-axially
to each other, a first part 11a protruding outside the containing
body 34 and a second part 11b placed inside the containing body
34,
[0034] an electromagnetic unit 12 placed inside, or comprising, the
containing body 34 and coaxial to the central element 11, and
[0035] a rear closing ring-nut 13 which closes the containing body
34 at the opposite side with respect the protruding part 11a of the
central element 11.
[0036] The central element 11 and the ring-nut 13 are
advantageously made, by means of molding, of amagnetic material,
for example of plastic material.
[0037] According to a feature of the invention, a circular flange
18 is made in one piece between the first part 11a and the second
part 11b and allows to directly mount the central element 11 to the
containing body 34 without needing any auxiliary ring or seal.
[0038] According to a further characteristic feature of the present
invention, the first part 11a of the central element 11, which
exits from the containing body 34 and from the electromagnetic unit
12, is configured to be coupled directly, or indirectly, to the
different hydraulic devices downstream thereof.
[0039] To be more exact, such first part 11a comprises a
substantially cylindrical, smooth and non-threaded terminal segment
and an attachment zone in which a circumferential groove 42 is
made, into which an elastic clip 40 is able to be arranged. In this
way the pump 10 can be directly connected to those hydraulic
devices that have a substantially cylindrical mouthpiece.
[0040] In order to connect the pump 10 to hydraulic devices with a
different mouthpiece, at least one optional connector 15 is also
provided, also made of amagnetic material, which is able to be
associated with the first part 11a of the central element 11 and
which will be described in detail hereafter.
[0041] The central element 11 is shaped so as to have inside it two
coaxial through cavities 16a and 16b, in correspondence with the
parts 11a and 11b respectively. A core 17, made of ferromagnetic
material, whose functioning will be explained hereafter, is
arranged in a sliding manner inside the low-pressure cavity 16b,
which has a greater diameter than that of cavity 16a. Inside the
high-pressure axial cavity 16a, a wall 19 is provided which reduces
the section and is able to define an accumulation chamber 20.
[0042] The ferromagnetic core 17 is axially connected to a first
shutter 30, substantially formed by a rubber block, arranged in the
cavity 16a and put in cooperation with the reducing wall 19. To be
more exact, between the shutter 30 and the wall 19, a spring 32 is
arranged, able to normally push such shutter 30 towards the
ferromagnetic core 17, in order to allow the fluid to pass through
the reducing wall 19.
[0043] A second shutter 31 is arranged in the accumulation chamber
20, held towards the reducing wall 19 by a spring 33 arranged
between such shutter 31 and an internal shoulder of the first part
11a of the central element 11. Advantageously, such internal
shoulder 41 is made by riveting the extremity of the first part
11a.
[0044] A bushing 45 (FIGS. 2 and 3), made of brass or other metal
material, is inserted, for example driven, between the axial
cavities 16a and 16b, and acts as a separator between the
high-pressure and the low-pressure zones, in order to prevent the
pressure generated by the oscillations of the core from being
eliminated by a reflow outside the core. Furthermore, a sealing
ring 46, for example made of fluoridized plastic material, is
arranged between the bushing 45 and the cavity 16a, and associated
with an elastic ring 47. An elastic ring 48, for example made of
elastomeric material, is instead arranged between the bushing 45
and the cavity 16b, and functions as an end-of-travel element for
the core 17 and reduces the noise thereof.
[0045] The electromagnetic unit 12, which is advantageously
produced separately before being assembled on the second part 11b
of the central element 11, comprises a reel 24 made of plastic
material arranged concentric to such second part 11b, that is, in
correspondence with the segment where the ferromagnetic core 17
slides. An electric coil 21 is arranged around the reel 24, able to
be fed with alternating current in order to generate a pulsating
magnetic field. The electromagnetic unit 12 also comprises a
ferromagnetic structure 28 arranged around the coil 21 and
partially interposed between the reel 24 and the central element
11.
[0046] At the front, the ferromagnetic structure 28 rests against
the circular flange 18 of the central element 11, in this way
defining a positioning wall for the electromagnetic unit 12 with
respect to the central element 11.
[0047] The electromagnetic unit 12 is drowned in the containing
body 34 of plastic material. Such containing body 34 has a front
wall 34a against which the circular flange 18 abuts, so as to
guarantee an excellent electric insulation of the ferromagnetic
parts of the pump 10. Furthermore, two electric terminals 22 are
fixed to the front wall 34a, to supply the electric feed for the
electric coil 21.
[0048] The pulsating magnetic field generated by the electric coil
21 induces, in the known manner, the ferromagnetic core 17 to slide
alternately and axially inside the axial cavity 16b. By doing this,
the ferromagnetic core 17 alternately moves the shutter 30, in
order to piston pump the fluid towards the accumulation chamber 20
and, at the same time, increase the pressure thereof.
[0049] The rear ring-nut 13 comprises a substantially tubular part
23 and a flange 26.
[0050] The tubular part 23 is provided with an external surface 23a
connecting it to a pipe, or other external element, in order to
allow the entrance of the fluid that has to be taken under pressure
into the pump 10. The ring-nut 13, in fact, has a through hole 25
arranged concentric to the axial cavity 16b, and able to connect
the latter with the exterior.
[0051] Such tubular part 23 also has an internal thread 23b made in
a zone close to the flange 26, so that the ring-nut 13 can be
screwed to the second part 11b of the central element 11.
[0052] The flange 26 of the ring-nut 13 is made in one piece with
the tubular part 23 and has the double function of covering and
totally insulating the rear part of the ferromagnetic structure 28
of the electromagnetic unit 12, and of maintaining the latter in
abutment against the circular flange 18 of the central element
11.
[0053] The ring-nut 13 also has a abutment surface 27, facing
towards the axial cavity 16b, against which the end of a helical
spring 29 rests, with the other end in contact with the core 17, in
order to normally maintain the latter in a position distant from
the ring-nut 13, with the shutter 30 moved towards the reducing
wall 19.
[0054] As shown in FIG. 2, the external structure of the
electromagnetic unit 12 consists completely of elements made of
plastic material which, in cooperation with the flanges 18 and 26,
also made of plastic material, totally protect the ferromagnetic
components present inside such electromagnetic unit 12, thus
insulating and optimizing the electromagnetic circuit of the pump
10.
[0055] Furthermore, the thread 23b made on the ring-nut 13 allows
the different components to be assembled quickly and simply,
noticeably reducing the production costs of the pump 10.
[0056] The optional connector 15 comprises an internal surface 35
with a profile mating that of the first part 11a of the central
element 11, and an external surface 36 shaped so as to be coupled
with other corresponding standard mouthpieces of other hydraulic
devices present on the market. The connector 15 also comprises an
exit pipe 37 coaxial to the accumulation chamber 20, and a
circumferential slot 39, which when in use overlaps the groove 42
and inside which the elastic clip 40, which guarantees the coupling
of the connector 15 to the central element 11, is able to be
arranged.
[0057] Such clip 40 can be selectively removed in order to allow
the connector 15 to be detached from the central element 11. In
this way it is possible to replace the connector 15 with another
connector 15, similar to the first but with an external surface 36
with a different profile.
[0058] In this way, it is possible to couple the pump 10 according
to the invention with different types or models of hydraulic
devices simply by replacing the connector 15, according to the
attachment profile of such hydraulic devices.
[0059] We thus obtain the advantage of having a pump wherein the
elements that form it (and particularly the part 11a where the
fluid exits) are the same in any type of hydraulic device that has
to be coupled downstream thereof, and wherein a simple adaptor
element (in this specific case the connector 15) is able to be
optionally associated with the part 11a where the fluid exits, in
order to allow it to be connected also to those hydraulic devices
which are not already provided with a mouthpiece mating that of
said part 11a where the fluid exits.
[0060] It is clear, however, that modifications and/or additions of
parts can be carried out to the pump 10 described heretofore,
without departing from the field and scope of the present
invention.
[0061] For example, the clip 40 and the relative slot 39 and groove
42 can be replaced by any other removable clamping means, such as
for example a bayonet joint, an elastic tooth, a screw, or other.
Furthermore, sealing packings of a known type can be provided,
according to necessity, arranged so as to make the coupling between
the various elements water tight.
[0062] Furthermore, the terminal segment of the first part 11a of
the central element 11 can have an external profile other than
cylindrical, and be for example of the type mating with a
corresponding attachment profile of a determinate hydraulic device,
in order to allow the direct connection of the pump 10 and said
hydraulic device.
[0063] It is also clear that, although the invention has been
described with reference to a specific example, a person of skill
in the art shall be able to achieve other forms of electromagnetic
pump with oscillating core, all of which shall come within the
field and scope of the present invention.
* * * * *