US1726394A - Duplex electromagnetic vibratory unit - Google Patents

Duplex electromagnetic vibratory unit Download PDF

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US1726394A
US1726394A US111456A US11145626A US1726394A US 1726394 A US1726394 A US 1726394A US 111456 A US111456 A US 111456A US 11145626 A US11145626 A US 11145626A US 1726394 A US1726394 A US 1726394A
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sleeve
pole pieces
magnetic
armature
flanges
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Heusser Wilfrid
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R11/00Transducers of moving-armature or moving-core type

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  • This invention relates to a duplex electromagnetic vibratory unit especially for use as a loud speaker, and its principal ob ects are to provide an instrument which shall:
  • Fig. 1 represents a top plan
  • FIG. 2 an elevation in the direction of the arrow 2, Fig. 1;
  • FIG. 3 a section on line 3, Fig. 1;
  • FIG. 4 a fragmentary section on line 4:, Fig. 1;
  • FIG. 5 details of the spool structure and pole pieces only, Fig. 5 being a section on line 5, Fig. 7;
  • Fig. 6, a section on line 6, Fig. 5;
  • Fig. 7 an elevation in the direction of arrow 7, Fig. 5;
  • 40 indicates a base having the ferrule 11 for connecting to the usual horn *or other amplifying device (not shown).
  • a cap 44 which latter is recessed to receive the diaphragm l5 as well as the raised annular portion 46 of the base which bears against the circumferential margin of the diaphragm.
  • Screws 4? have the body 48 shouldered to bear against the lower face of cap 14 and are drawn tightly against the face of the cap by means of the threaded end 49.
  • Springs 50 exert uniform pressure upon the marginal bearing area of the diaphragm, thereby eliminating evils resulting from gripping the diaphragm too tightly, or having it too loose, especially from changes in temperature.
  • U-shaped permanent magnets 31 having their poles 31 of the same polarity opposed to, and slightly spaced apart from, each other. These magnets are clamped down tightly by means of the U-bolts 52, whose legs 53 pass through holes in the cap 44 and secured by the nuts 5 the latter being disposed in blind recesses in the under side of the cap. Lugs 42 having holes -13 may be provided for fastening the cap to any suitable supporting structure such as a cabinet.
  • the spool 55 which has a number of new features, and forms an important part of the electromagnet.
  • the spool 55 is made up of the body sleeve 10 (Figs. 5 to S) and the body flanges 12 which parts may be made of non-magnetic material such as brass, and be united to each other by soldering their contacting surfaces to each other as at 56.
  • Pole pieces 57 preferably made of silicon steel, extend through the sleeve from end to end, substantially parallel to the surfaces of the armature (Figs. 2 and 3) in its neutral position. Each pole piece may be united to the corresponding inner surface of the sleeve by soldering, as at 58.
  • the magnetic conductors 14 and 14 In intimate contact with the pole pieces 57, are the magnetic conductors 14 and 14 which may be made of iron and held rigidly in place by soldering as at 60, to the flanges 12 of the spool.
  • Pins 17 are rigidly fastened in the pole pieces and sleeve, and have the notched faces 19 for receiving the armature.
  • the armature is held in place by means of the spring rigging, consisting of the tie 26, the yoke 27, and the spring bar 28 having cradles 3O integral with the legs 30 which are mounted in the spool as indicated in Figs. 1, 2 and 3, and as described in detail in my other application for patent, previously mentioned herein.
  • a gap 6]. may be cut through the flanges and. sleeve of the spool, bifurcating it to admit the tie 26 and to prevent the Vforma tion of transformer currents in the spool structure due to the action of the electromagnet coil.
  • Fig. 6 The position of the armature within the spool is indicated by dotted lines in Fig. 6, which, together with the showing in Figs. 2 and 3, makes clear the fact that the main superficial area of the armature is substantially equal to, and superposed in registry with, the main superficial areas of the pole pieces, so that the magnetic flux in bridging the gap from one-set of pole pieces to the other set, virtually permeates the armature at every point thereof.
  • the magnetic flux from one pair of similar poles of both permanent magnets follows the conductors to and through the corresponding pole piece, and is applied over substantially the entire superposed and registering area of the armature, as just described, reaching the opposite pair of similar poles through the armature, through the opposite pole piece and through the opposite conductor, thus completing the magnetic circuit.
  • This arrangement makes extremely favorable use of the magnetic energy.
  • the coil 62 of the electromagnet is wound upon the spool 55 and the electromagnet action is such that the pole pieces and the armature are inductively influenced simultaneously, with the result that slight variations in the electric current exercise a relatively large unbalancing effect on the armature and hence on the diaphragm also.
  • An electromagnetic vibratory unit comprising an oscillating armature, pole'pieces having their principal superficial areas lying in planes on opposite sides of, and substantially parallel to, the plane of said armature in its neutral position, a source of magnet ism, an armature operatively positioned between the said pole pieces, and an electromagnet arranged to inductively influence said armature.
  • An electromagnetic vibratory unit comprising a permanent magnet, pole pieces substantially parallel to each other, an arma ture operatively positioned between the pole pieces, an electro-magnetic coil arranged to influence said armature and pole pieces simultaneously, and magnetic conductors extending from the poles of said permanent magnet to the said pole pieces.
  • An electromagnetic vibratory unit comprising an electro-magnetic coil having an aperture therethrough, an armature operatively positioned within said aperture, pole pieces spaced apart from and paralleling said armature on either side thereof, and a source of magnetism arranged to maintain a magnetic flux in said pole pieces.
  • An electromagnetic vibratory unit com prising an electro-magnetic coil having an aperture substantially through the center of winding thereof, an armature mounted to oscillate within said aperture, pole pieces substantially paralleling the said armature in its neutral position, and means for establishing a magnetic flux in said pole pieces.
  • An electromagnetic vibratory unit comprising a coil having a sleeve, pole'pieces spaced apart from and paralleling each other within said sleeve, forming integral parts thereof; flanges at both extremities of said sleeve, magnetic conductors closely contactlng said pole pieces and forming integral parts of said flanges, and U-shaped permanent magnets having their poles contacting the said conductors.
  • An electromagnetic vibratory unit comprising Ushape permanent magnets, a spool held between the legs thereof, said spool having a non-magnetic sleeve, pole pieces lying wholly in planes paralleling said sleeve, magnetic conductors extending from said magnets to said pole pieces, a supporting structure for said magnets, and means holding said magnets upon said structure.
  • An electromagnetic vibratory unit comprising an armature, pole pieces spaced apart G from, and paralleling said armature, on either side thereof, said pole pieces substantially overlying the major superficial face of the armature, and an induction coil for simultaneously magnetizing said armature and said pole pieces.
  • An electromagnetic vibratory unit comprising an armature, pole pieces spaced apart from, and paralleling said armature, on either side thereof, a permanent source of magnet-ism arranged to influence said armature, and a source of electromagnetism arranged to simultaneously influence the said armature and the said pole pieces.
  • An electromagnetic vibratory unit comprising a base, a cap mounted thereon, an armature having a marginal bearing between said cap and base, means for maintaining a uniform pressure upon said bearing, permanent magnets mounted on said cap, an electro-magnetic coil held by said permanent magnets, an armature within the said 0011 pole pieces, paralleling said armature so armature and pole pieces will be simultaneously influenced by said coil, conductors from said magnets to said pole pieces, and a connection from said armature to said dia phragm.
  • a spool comprising asleeve, flanges at either end of said sleeve, upper and lower pole pieces substantially identical with the upper and lower portions of said sleeve, and magnetic conductors substantially identical with said flanges, said conductors being in close contact with said pole pieces.
  • a spool comprising a sleeve, flanges at either end of said sleeve, upper and lower pole pieces substantially identical with the upper and lower portions of said sleeve, and magnetic conductors substantially identical with said flanges, said sleeve, flanges, pole pieces and magnetic conductors being bifurcated.
  • a spool structure having a sleeve, upper and lower pole pieces substantially in tegral with said sleeve, said sleeve being made of non-magnetic material, means for mounting an oscillating armature within said sleeve, and means for holding an electromagnetic coil on said sleeve.
  • a spool comprising a non-magnetic sleeve, non-magnetic flanges fastened to op; posite ends of the sleeve, pole pieces fastened opposite each other within said sleeve, and magnetic conductors extending from said pole pieces outwardly along said flanges.
  • a spool comprising a non-magnetic sleeve, non-magnetic flanges fastened to the sleeve at opposite ends thereof, pole pieces fastened within said sleeve in opposite relation to each other, and magnetic conductors in magnetic contact with said pole pieces, as
  • said magnetic conductors being contiguous to said anges.
  • a spool comprising a non-magnetic sleeve having two opposite plane portions, non-magnetic flanges fastened to the sleeve at opposite ends thereof, plane pole pieces fastened to the plane portions of said sleeve along contiguous surfaces thereof, and magnetic conductors extending from said pole pieces outwardly along said flanges.
  • a spool comprising a non-magnetic sleeve having two opposite substantially plane surfaces defined therein, non-magnetic flanges fastened to the sleeve at opposite ends thereof, substantially plane pole pieces soldered to the plane surfaces of said sleeve, and substantially plane magnetic conductors soldered to the said flanges along contiguous surfaces thereof.
  • a spool comprising a non-magnetic sleeve, non-magnetic flanges fastened to opposits ends of the sleeve, pole pieces fastened opposite each other within said sleeve, and magnetic conductors extending from said pole pieces outwardly along said flanges, said spool being bifurcated to define a gap extending through said sleeve, pole pieces, flanges and conductors.
  • a spool comprising a non-magnetic sleeve, non-magnetic flanges fastened to the sleeve at opposite ends thereof, pole pieces fastened within said sleeve in opposite relation to each other, and magnetic conductors in magnetic contact with said sole pieces, as well as contiguous to said flanges; said sleeves, flanges, pole pieces and conductors having a co-extending gap defined therein.
  • a spool comprising a non-magnetic sleeve having two opposite plane portions, non-magnetic flanges fastened to the sleeve at opposite ends thereof, plane pole pieces fastened to the plane portions of said sleeve along contiguous surfaces thereof, magnetic conductors extending from said pole pieces outwardly along said flanges; and a gap defined across said spool, said gap extending through said sleeve, pole pieces, flanges and conductors.
  • a spool comprising a non-magnetic sleeve having two opposite substantially plane surfaces defined therein, non-magnejic flanges fastened to the sleeve at opposite ends thereof, substantially plane pole pieces soldered to the plane surfaces of said sleeve, substantially plane magnetic conductors soldered to the said flanges along contiguous surfaces thereof; and a gap defined across said spool.
  • VILFRID HEUSSER VILFRID HEUSSER.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Electromagnets (AREA)

Description

Aug. 27, 1929. w. HEUSSER DUPLEX ELECTROMAGNETIC nsm'rom UNIT Filed May 24, 1926 glwuzntoo fi S Hts-2135512,
KNEE
Guam;
Patented Aug. 27, 1929.
UNITED STATES WILFRID HEUSSER, OF SALT LAKE CITY, UTAH.
DUPLEX ELECTROMAGNETIC VIBRATORY UNIT.
Application filed May 24,
This invention relates to a duplex electromagnetic vibratory unit especially for use as a loud speaker, and its principal ob ects are to provide an instrument which shall:
First. Be faithfully responsive to the most delicate tones and tone variations.
Second. Be equally as responsive to the heavy tones with extreme variations.
Third. Be sturdy in construction and therefore free from operating troubles.
Fourth. Keep the vibratory member or members free from a super-imposed tension- Tifth. Be compact, and simple to manufacture.
These objects are attained to an eminent degree by (a) distributing the magnetic flux, operative on an armature, over substantially the entire main superficial area thereof, instead of concentrating the flux on only fractional parts of this area; (b) constructing the spool of the electromagnet in a novel manner to obtain strength, and to accommodate the pole pieces and magnetic conductors by which the unique distribution of the flux is accomplished; (c) magnetizing the pole pieces by induction simultaneously w th the armature, in addition to the magnetization thereof by the usual permanent magnet; (cl) mounting the diaphragm so that the pressure of the confining members shall be uniform under all temperature conditions.
The armature and mounting constituting the subject of a separate application for U. S. patent filed by me September 24, 1926, Serial No. 111.455, is designed to be used in conjunction with the present invention, for obtaining the best results.
The features of this invention for which the protection of Letters Patent is desired, are collectively grouped in the claims which conclude this specification.
In the drawing, illustrating merely one embodiment of this invention:
Fig. 1 represents a top plan;
Fig. 2, an elevation in the direction of the arrow 2, Fig. 1;
Fig. 3, a section on line 3, Fig. 1;
Fig. 4, a fragmentary section on line 4:, Fig. 1;
Figs. 5 to 8, details of the spool structure and pole pieces only, Fig. 5 being a section on line 5, Fig. 7;
1926. Serial No. 111,456.
Fig. 6, a section on line 6, Fig. 5;
Fig. 7, an elevation in the direction of arrow 7, Fig. 5;
Fig. 8, a section on line 8, Fig. 5, part broken away.
Referring to the drawing, 40 indicates a base having the ferrule 11 for connecting to the usual horn *or other amplifying device (not shown).
Mounted on the base is a cap 44: which latter is recessed to receive the diaphragm l5 as well as the raised annular portion 46 of the base which bears against the circumferential margin of the diaphragm. Screws 4? have the body 48 shouldered to bear against the lower face of cap 14 and are drawn tightly against the face of the cap by means of the threaded end 49. Springs 50 exert uniform pressure upon the marginal bearing area of the diaphragm, thereby eliminating evils resulting from gripping the diaphragm too tightly, or having it too loose, especially from changes in temperature.
On the cap 414 are mounted U-shaped permanent magnets 31 having their poles 31 of the same polarity opposed to, and slightly spaced apart from, each other. These magnets are clamped down tightly by means of the U-bolts 52, whose legs 53 pass through holes in the cap 44 and secured by the nuts 5 the latter being disposed in blind recesses in the under side of the cap. Lugs 42 having holes -13 may be provided for fastening the cap to any suitable supporting structure such as a cabinet.
Held between the legs of the magnets 31 place by bolts 52, is the spool 55, which has a number of new features, and forms an important part of the electromagnet. The spool 55 is made up of the body sleeve 10 (Figs. 5 to S) and the body flanges 12 which parts may be made of non-magnetic material such as brass, and be united to each other by soldering their contacting surfaces to each other as at 56. Pole pieces 57, preferably made of silicon steel, extend through the sleeve from end to end, substantially parallel to the surfaces of the armature (Figs. 2 and 3) in its neutral position. Each pole piece may be united to the corresponding inner surface of the sleeve by soldering, as at 58.
In intimate contact with the pole pieces 57, are the magnetic conductors 14 and 14 which may be made of iron and held rigidly in place by soldering as at 60, to the flanges 12 of the spool. Pins 17 are rigidly fastened in the pole pieces and sleeve, and have the notched faces 19 for receiving the armature. The armature is held in place by means of the spring rigging, consisting of the tie 26, the yoke 27, and the spring bar 28 having cradles 3O integral with the legs 30 which are mounted in the spool as indicated in Figs. 1, 2 and 3, and as described in detail in my other application for patent, previously mentioned herein.
A gap 6]. may be cut through the flanges and. sleeve of the spool, bifurcating it to admit the tie 26 and to prevent the Vforma tion of transformer currents in the spool structure due to the action of the electromagnet coil.
The position of the armature within the spool is indicated by dotted lines in Fig. 6, which, together with the showing in Figs. 2 and 3, makes clear the fact that the main superficial area of the armature is substantially equal to, and superposed in registry with, the main superficial areas of the pole pieces, so that the magnetic flux in bridging the gap from one-set of pole pieces to the other set, virtually permeates the armature at every point thereof.
In operation, the magnetic flux from one pair of similar poles of both permanent magnets, follows the conductors to and through the corresponding pole piece, and is applied over substantially the entire superposed and registering area of the armature, as just described, reaching the opposite pair of similar poles through the armature, through the opposite pole piece and through the opposite conductor, thus completing the magnetic circuit. This arrangement makes extremely favorable use of the magnetic energy.
The coil 62 of the electromagnet is wound upon the spool 55 and the electromagnet action is such that the pole pieces and the armature are inductively influenced simultaneously, with the result that slight variations in the electric current exercise a relatively large unbalancing effect on the armature and hence on the diaphragm also.
Uusing two permanent magnets arranged as clearly shown in Fig. 2, produces an inde pendent magnetic circuit in each half of the said unit and results in a particularly strong and advantageous magnetic action upon the armature, whose motion is transmitted to the diaphragm through tie 70.
While a specific embodiment of this invention is herein shown and described, it is to be clearly understood that the detailed parts thereof, may, or may not, be shown in the preferred forms, and further, that the preferred forms may be varied from time to time, as the development of this invention and the arts with which it is identified, progress. Therefore, that which forms an essential and characteristic part of this invention will be readily discernible from the claims in which its spirit is generalized.
Having fully described my invention what I claim is:
1. An electromagnetic vibratory unit, comprising an oscillating armature, pole'pieces having their principal superficial areas lying in planes on opposite sides of, and substantially parallel to, the plane of said armature in its neutral position, a source of magnet ism, an armature operatively positioned between the said pole pieces, and an electromagnet arranged to inductively influence said armature.
An electromagnetic vibratory unit comprising a permanent magnet, pole pieces substantially parallel to each other, an arma ture operatively positioned between the pole pieces, an electro-magnetic coil arranged to influence said armature and pole pieces simultaneously, and magnetic conductors extending from the poles of said permanent magnet to the said pole pieces.
3. An electromagnetic vibratory unit comprising an electro-magnetic coil having an aperture therethrough, an armature operatively positioned within said aperture, pole pieces spaced apart from and paralleling said armature on either side thereof, and a source of magnetism arranged to maintain a magnetic flux in said pole pieces.
4. An electromagnetic vibratory unit com prising an electro-magnetic coil having an aperture substantially through the center of winding thereof, an armature mounted to oscillate within said aperture, pole pieces substantially paralleling the said armature in its neutral position, and means for establishing a magnetic flux in said pole pieces.
5. An electromagnetic vibratory unit comprising a coil having a sleeve, pole'pieces spaced apart from and paralleling each other within said sleeve, forming integral parts thereof; flanges at both extremities of said sleeve, magnetic conductors closely contactlng said pole pieces and forming integral parts of said flanges, and U-shaped permanent magnets having their poles contacting the said conductors. I
6. An electromagnetic vibratory unit comprising Ushape permanent magnets, a spool held between the legs thereof, said spool having a non-magnetic sleeve, pole pieces lying wholly in planes paralleling said sleeve, magnetic conductors extending from said magnets to said pole pieces, a supporting structure for said magnets, and means holding said magnets upon said structure.
7. An electromagnetic vibratory unit comprising an armature, pole pieces spaced apart G from, and paralleling said armature, on either side thereof, said pole pieces substantially overlying the major superficial face of the armature, and an induction coil for simultaneously magnetizing said armature and said pole pieces.
8. An electromagnetic vibratory unit comprising an armature, pole pieces spaced apart from, and paralleling said armature, on either side thereof, a permanent source of magnet-ism arranged to influence said armature, and a source of electromagnetism arranged to simultaneously influence the said armature and the said pole pieces.
9. An electromagnetic vibratory unit comprising a base, a cap mounted thereon, an armature having a marginal bearing between said cap and base, means for maintaining a uniform pressure upon said bearing, permanent magnets mounted on said cap, an electro-magnetic coil held by said permanent magnets, an armature within the said 0011 pole pieces, paralleling said armature so armature and pole pieces will be simultaneously influenced by said coil, conductors from said magnets to said pole pieces, and a connection from said armature to said dia phragm.
10. A spool comprising asleeve, flanges at either end of said sleeve, upper and lower pole pieces substantially identical with the upper and lower portions of said sleeve, and magnetic conductors substantially identical with said flanges, said conductors being in close contact with said pole pieces.
11. A spool comprising a sleeve, flanges at either end of said sleeve, upper and lower pole pieces substantially identical with the upper and lower portions of said sleeve, and magnetic conductors substantially identical with said flanges, said sleeve, flanges, pole pieces and magnetic conductors being bifurcated.
12. A spool structure having a sleeve, upper and lower pole pieces substantially in tegral with said sleeve, said sleeve being made of non-magnetic material, means for mounting an oscillating armature within said sleeve, and means for holding an electromagnetic coil on said sleeve.
13. A spool comprising a non-magnetic sleeve, non-magnetic flanges fastened to op; posite ends of the sleeve, pole pieces fastened opposite each other within said sleeve, and magnetic conductors extending from said pole pieces outwardly along said flanges.
I 14. A spool comprising a non-magnetic sleeve, non-magnetic flanges fastened to the sleeve at opposite ends thereof, pole pieces fastened within said sleeve in opposite relation to each other, and magnetic conductors in magnetic contact with said pole pieces, as
said magnetic conductors being contiguous to said anges.
15. A spool comprising a non-magnetic sleeve having two opposite plane portions, non-magnetic flanges fastened to the sleeve at opposite ends thereof, plane pole pieces fastened to the plane portions of said sleeve along contiguous surfaces thereof, and magnetic conductors extending from said pole pieces outwardly along said flanges.
16. A spool comprising a non-magnetic sleeve having two opposite substantially plane surfaces defined therein, non-magnetic flanges fastened to the sleeve at opposite ends thereof, substantially plane pole pieces soldered to the plane surfaces of said sleeve, and substantially plane magnetic conductors soldered to the said flanges along contiguous surfaces thereof.
17. A spool comprising a non-magnetic sleeve, non-magnetic flanges fastened to opposits ends of the sleeve, pole pieces fastened opposite each other within said sleeve, and magnetic conductors extending from said pole pieces outwardly along said flanges, said spool being bifurcated to define a gap extending through said sleeve, pole pieces, flanges and conductors.
18. A spool comprising a non-magnetic sleeve, non-magnetic flanges fastened to the sleeve at opposite ends thereof, pole pieces fastened within said sleeve in opposite relation to each other, and magnetic conductors in magnetic contact with said sole pieces, as well as contiguous to said flanges; said sleeves, flanges, pole pieces and conductors having a co-extending gap defined therein.
19. A spool comprising a non-magnetic sleeve having two opposite plane portions, non-magnetic flanges fastened to the sleeve at opposite ends thereof, plane pole pieces fastened to the plane portions of said sleeve along contiguous surfaces thereof, magnetic conductors extending from said pole pieces outwardly along said flanges; and a gap defined across said spool, said gap extending through said sleeve, pole pieces, flanges and conductors.
20. A spool comprising a non-magnetic sleeve having two opposite substantially plane surfaces defined therein, non-magnejic flanges fastened to the sleeve at opposite ends thereof, substantially plane pole pieces soldered to the plane surfaces of said sleeve, substantially plane magnetic conductors soldered to the said flanges along contiguous surfaces thereof; and a gap defined across said spool.
In testimony whereof, I sign my name hereto.
VILFRID HEUSSER.
US111456A 1926-05-24 1926-05-24 Duplex electromagnetic vibratory unit Expired - Lifetime US1726394A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1994002952A1 (en) * 1992-07-15 1994-02-03 Lord Corporation Method and apparatus for making electrical connection with a movable member

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1994002952A1 (en) * 1992-07-15 1994-02-03 Lord Corporation Method and apparatus for making electrical connection with a movable member
US5323133A (en) * 1992-07-15 1994-06-21 Lord Corporation Method and apparatus for making electrical connection with a movable member

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