US1228226A - Diaphragm-horn. - Google Patents

Diaphragm-horn. Download PDF

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Publication number
US1228226A
US1228226A US81080114A US1914810801A US1228226A US 1228226 A US1228226 A US 1228226A US 81080114 A US81080114 A US 81080114A US 1914810801 A US1914810801 A US 1914810801A US 1228226 A US1228226 A US 1228226A
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Prior art keywords
diaphragm
armature
horn
wall
rotor
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Expired - Lifetime
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US81080114A
Inventor
Duncan A Mcconnell
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Lovell McConnell Manufacturing Co
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Lovell McConnell Manufacturing Co
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    • GPHYSICS
    • G10MUSICAL INSTRUMENTS; ACOUSTICS
    • G10KSOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K9/00Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers
    • G10K9/10Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers driven by mechanical means only

Definitions

  • This invention relates to certain improvements in diaphragm horns and more particularly to that type in which the shaft is presented endwise to the diaphragm and carries the rotor for vibrating said diaphragm.
  • One of the main objects of my present invention is to provide simple and efiicient means for insuring the maintenance of the shaft in the desired adjusted position.
  • my invention in a type of horn similar in many respects to that disclosed and claimedin my prior Patent No. 1,160,902, granted November 16th, 1915, on an application filed April 2, 1913.
  • One feature of my present invention involves an improved and simplied form of motor frame adaptable for use. in a horn of the character disclosed in said prior application.
  • Figure l is a central longitudinal section of a horn embodying my invention, said section being taken on the line 1-1 of Fig. 4, a part of the resonator being broken away;
  • Fig. 2 is an inverted plan view, the motor casing and support being shown in section and the diaphragm and resonator being removed;
  • Figs. 3 and 4 are sections on the lines 3--3 and i-4, respectively, of Fig. 1.
  • the diaphragm is illustrated as being held between the annular peripheral portions 12 and 13 of two diaphragm casing sections 14 and l5.
  • Nashers 16 of cork, fiber or other non-vibratory material are preferably interposed between the diaphragm and the faces of the clamping sections and suitable bolts or screws 17, hold the diaphragm casing sections, the
  • the front casing section 14 has a. large central opening and presents an annular ilange 18 to which the resonator may be secured
  • the diaphragm at its cen-- ter or in the vicinity thereoris provided with a suitable wear-piece 19 ada ted to be engaged by the rotor to give the the desired vibrations. and mounting of the diaphragm does not involve any portion of my invention and may be varied or changed without in any way departing from the spirit of my invention.
  • armature shaft carries a rotor 21 in the forni of a face cam or ratchet having projections, corrugations, irregularities. or teeth adapted to successively engage with the wear-piece 19 or other thrust member.
  • the eccentricity of the armature shaft is substantially equal to the effective radius vof the rotor, although it is evident that any otherl suitable and well-known means maybe employed, for transmitting motion from the operating face of the rotor to the center of the diaphragm.
  • the particular arrangement of rotor and wear-piece ⁇ illustrated constitute no portion of my invention, and therefore any other suitable means may be employed in place of that shown for securing the vibration of the diaphragm upon the rotor of the armature shaft.
  • the rear diaphragm casing section 15 is in the form 'of a disheddisk and includes a transverse wall 22 s aced from the diaphragm and substantia ly parallel thereto and connected to the clamping portion 12 by an annular peripheral wall including a cylindrical portion 23 and an in ⁇ clined or conical portion 24.
  • the transverse wall 22- is spaced from the diaphragm a suiicient distance to permit the positioning of the rotor and wear-piece therebetween and permit the proper vibration of the diaphragm.
  • This casing section has the transverse wall 22 provided with an opening 25 through which the wires or other conductors may freely extend.
  • This transverse wall 22 serves vas a bearing' for onel ond of the armature shaft 2()I and for supporting the opposite end I provide a substantially U-shaped frame member having side legs or bars 26 and 27 e2;-
  • aphragm The construction tending rearwardly from the wall Q2 and a transverse portion 28 substantially parallel to the wall 22 but spaced therefrom and :termed integral with the side bars 26 and 2T. 5
  • the two' parts may be secured together' in any suitable manner as for instance by screws Q9 extending through the wall 22 into the ends oit' the side bars 26 and. 27.
  • the two side bars Q6 and 27 serve to snpport the pole pieces of the motor and infact may have inwardly projecting portions imiegral therewith and constituting said pole pieces.
  • the ield coils 3l are preferably made up separately and after being provided with suitable casings to hold the separate wires of the coil together may beislipped on over the poleepieces prior to the placing ot' the armature 32 there-between.
  • the motor may be very easily assembled by irst slipping the coils over the pole-pieces, then inserting the armature thereon, and then securing the U-shaped frame member to the wail 22 by means of the screws 2S).
  • I For holding the coils in position upon the polepieces and preventing their slipping inwai-dy or becoming accidently displaced, so as to contact with the armature, I provide suitable spring clips 42 which may extend across from one coil tothe other and may be held from inward movement by engaging with the pole-pieces.
  • Ilhe transverse member 28 of the motor frame is provided with a bridge 34 on its side away from the diaphragm, and the entire bridge is preferably integral with the motor trame.
  • the two legs 33 and 35 o'tl the. bridge have alined openings substantially parallel to the transverse portion 2S of "the motor iframe, and within these openings are brushes 3G which are adjustable and are held in place in any suitable manner, as for instance by screws extending inwardly from the outer surface ot the transverse member of the bridge.
  • the commutator is located between the two legs on the bridge, and is thus readily accessible from each side.
  • YIwo insniated wires 37 lead from the two coils to the outer ends of the two brushes and two insulated wires 38 lead from the coils through the opening 25 to terminals on the incl ined or conical wall 24.
  • the terminals limnay be et any suitable character. I have shown bolts extending through insulated bushings and having loclc nuts at the outer f end for retaining the Wires.
  • the end of the armature shaft preferably fits within a socket in the plug 48 screwed into the bridge 34, intermediate of the ends of the iatter.
  • This plug constitutes an adjustable thrust bearing, whereby the armature may bc 'forced endwise a limited distance toward the diaphragm to insure the proper contact ot the rotor with the diaphragm.
  • the armature and between the latter and the transverse wall 22 I provide a leaf-spring 50 which normally tends to force the armature back into contact with thc thrust bearing.
  • the specific vform of spring shown is a lcaf spring normally bowed and perforated at its center to receive the armature sha't't.
  • the ends of the spring engage with the transverse wall and the central portion engages with a washer or collar on the armature shaft or on the armature.
  • the spring will normally push the armature bach to such a position that the rotor will not properly contact with the wear-piece, but by means ol" the thrust bearing the armature and rotor are advanced until the proper engagement is secured and the armature is held between the spring and the thrust bearing.
  • the plug forming the thrust bearing may be held in place after adjusting, in any suitable manner, as for instance by a lock nut 4l. It preferably has an annular external groove communicating with an oil duct in the bridge as shown in Fig. 2. 'l' his groove communicates with the socket receiving the end of the armature shalt through a small passage as indicated in F ig. 1.
  • I may provide a small duct 43, leading downwardly from the cylindrical wall 23 of the bearing of the armature shaft and upon the side toward the diaphragm, so as not to interfere with the armature or coils.
  • I provide a thin casing 44 preferably of metal and preterably of cylindrical form. rlhe casing is shown as being ⁇ ot cl
  • the length oi this cylindrical wall determines the endwise sliding movement of the casing and the casing is preferably considerably smaller than the diaphragm, so that tlrc inclined wall serves not only to limit thex position ot the casing 44, but connects the, casing oiE small diameter to the diaphragm clamps ol larger diameter.
  • easing 44 also preferably covers the upper end of the oil duct 43 so as to protect the latter from dust and dirt.
  • the casing 44 may be taken oi and all ott ⁇ the parts of the motor will be exposed so that they may be adjusted, replaced or repaired without removing the motor from the horn.
  • the wires 38 from thc field coils through the opening 25 and mounting the terminals 46 on the inclined wall 24, it will be noted that the removal of the case 44 does not disturb the wiring connection to the motor and that the motor may be run and tested and its opffii eration noted with kthe casing removed.
  • Any snita le means may be employed for supporting the horn, for instance a bracket e7 ivhich may be secured to the diaphragm casl ing by two of the bolts, which hold the diaphragm clamping portions in position, as shcwn'in Fig.1 4s I thus described my invention, what i claim as new and desire to protect by Letters Patent, is;
  • a speed electric motor secured to said member and having its armature shaft j ournaled irl/said member and presented endtvpise to said diaphragm, a rotor carriedby shaft for effecting vibration of said diaphragm toward ahd from said rotor, an adjustable thrust bearing for limiting the axial rearward movement of said shaft and said rotor under the reaction of diaphragm, and a bowed leaf spring disposed between the armature of said motor and the rear surface of said member for main- Vdiaphragm case, the armature shaft of said electric motor extending through said plain rear 'wall and presented endivise to the diaphragm, ari-actuator mounted upont said armature shaft and disposed within the diaphragm case, an adjustable end thrust bearing for said armature shaft for moving lthe sametovvard the diaphragm, and a spring mounted on said shaft and having its end portions supported by said dia
  • a diaphragm In a horn, a diaphragm, a diaphragm case having a substantially plain rear Wall, an electric motor at the rear of said diaphragm case, the armature shaft of said electric motor extending through said plain rear Wall and presented endvvise to the diaphragm, an actuator mounted upon said armature shaft and disposed Within the diaphragin case, an adjustable end thrust bearing for said armature shaft for moving the same toward the diaphragm, and a spring mounted on said shaft and having its end portions supported by said diaphragm case and its intermediate portion bowed toward said end thrust bearing to maintain the armature shaft in engagement with said thrust bearing throughout the range of normal adjustment and operation ofthe device.
  • a horn a diaphragm, an electric motor at the rear of said diaphragm and having its armature shaft presented end- Wise to the diaphragm, a transverse wall between the armature of said motor and said diaphragm and through which said shaft extends, an actuator mounted upon saild armature shaft and disposed between said Wall and said diaphragm, an adjustable end thrustbearing for said armature shaft for moving the same toward the diaphragm and a spring mounted on said shaft and having its end portions supported by said Wall and an intermediate portion bowed toward said thrust bearing to normally hold the armature shaft the maximum distance from the diaphragm.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Multimedia (AREA)
  • Apparatuses For Generation Of Mechanical Vibrations (AREA)

Description

D. A. MCCONNELL.
DIAPHHAGM HORN.
APPLICATlo. EILED lAN. 7. 19m.
1,228,226. Emma my 29, 1917.
2 SHEETS-SHEET l.
, mi' It MIL Il', w n n By v 6i/@ATTORNEY D. A. MCCONNELL.
-DIAPHRAGM HORN.
APPLICATION HLED 1AN.7, 1914.
Pntemed May 29, 1917.
2 SHEETS-SHEET 2.
4mm/vn WIT/VESSES ,UNITED srrarns PATENT ornron.
DUNCAN MCCONNELL, 0F ARLINGTON, NEW JERSEY, ASSIGNOR "10 LOVELL- MCCONNELL MANUFACTURING COMPANY, OF NEWARK, N EW' JERSEY, A
CORPORATION OF DELAWARE.
DIAPHRAGM-HORN.
Specification of Letters Patent.
Patented May 29, 1917.
' Application filed January 7, 1914. Serial No. 810,801.
To all L12/wm t may concern.'
Be it known that I, DUNCAN A. McCoy- NnLL, a. citizen of the United States, and resident of Arlington, in the county of Hudson and State of New Jersey, have invented certain new and useful Improvements in Diaphragm-Horns, of which the following is a specification.
This invention relates to certain improvements in diaphragm horns and more particularly to that type in which the shaft is presented endwise to the diaphragm and carries the rotor for vibrating said diaphragm. One of the main objects of my present invention is to provide simple and efiicient means for insuring the maintenance of the shaft in the desired adjusted position. I have illustrated my invention in a type of horn similar in many respects to that disclosed and claimedin my prior Patent No. 1,160,902, granted November 16th, 1915, on an application filed April 2, 1913. One feature of my present invention involves an improved and simplied form of motor frame adaptable for use. in a horn of the character disclosed in said prior application.
Reference is to be had to the accompanying drawings, in which similar reference characters indicate corresponding parts throughout the several views.
Figure l is a central longitudinal section of a horn embodying my invention, said section being taken on the line 1-1 of Fig. 4, a part of the resonator being broken away;
Fig. 2 is an inverted plan view, the motor casing and support being shown in section and the diaphragm and resonator being removed; and
Figs. 3 and 4 are sections on the lines 3--3 and i-4, respectively, of Fig. 1.
I have illustrated my invention embodied in a horn employing a diaphragm 10 and a resonator or projector 11. The diaphragm is illustrated as being held between the annular peripheral portions 12 and 13 of two diaphragm casing sections 14 and l5. Nashers 16 of cork, fiber or other non-vibratory material, are preferably interposed between the diaphragm and the faces of the clamping sections and suitable bolts or screws 17, hold the diaphragm casing sections, the
washers and the diaphragm 1n the pro er relative positions. The front casing section 14 has a. large central opening and presents an annular ilange 18 to which the resonator may be secured The diaphragm at its cen-- ter or in the vicinity thereoris provided with a suitable wear-piece 19 ada ted to be engaged by the rotor to give the the desired vibrations. and mounting of the diaphragm does not involve any portion of my invention and may be varied or changed without in any way departing from the spirit of my invention.
'.ihe armature shaft carries a rotor 21 in the forni of a face cam or ratchet having projections, corrugations, irregularities. or teeth adapted to successively engage with the wear-piece 19 or other thrust member. The eccentricity of the armature shaftis substantially equal to the effective radius vof the rotor, although it is evident that any otherl suitable and well-known means maybe employed, for transmitting motion from the operating face of the rotor to the center of the diaphragm. The particular arrangement of rotor and wear-piece `illustrated constitute no portion of my invention, and therefore any other suitable means may be employed in place of that shown for securing the vibration of the diaphragm upon the rotor of the armature shaft.
Preferably the rear diaphragm casing section 15 is in the form 'of a disheddisk and includes a transverse wall 22 s aced from the diaphragm and substantia ly parallel thereto and connected to the clamping portion 12 by an annular peripheral wall including a cylindrical portion 23 and an in` clined or conical portion 24. The transverse wall 22- is spaced from the diaphragm a suiicient distance to permit the positioning of the rotor and wear-piece therebetween and permit the proper vibration of the diaphragm. This casing section has the transverse wall 22 provided with an opening 25 through which the wires or other conductors may freely extend.
This transverse wall 22 serves vas a bearing' for onel ond of the armature shaft 2()I and for supporting the opposite end I provide a substantially U-shaped frame member having side legs or bars 26 and 27 e2;-
aphragm The construction tending rearwardly from the wall Q2 and a transverse portion 28 substantially parallel to the wall 22 but spaced therefrom and :termed integral with the side bars 26 and 2T. 5 The two' parts may be secured together' in any suitable manner as for instance by screws Q9 extending through the wall 22 into the ends oit' the side bars 26 and. 27.
The two side bars Q6 and 27 serve to snpport the pole pieces of the motor and infact may have inwardly projecting portions imiegral therewith and constituting said pole pieces. The ield coils 3l are preferably made up separately and after being provided with suitable casings to hold the separate wires of the coil together may beislipped on over the poleepieces prior to the placing ot' the armature 32 there-between. Thus, the motor may be very easily assembled by irst slipping the coils over the pole-pieces, then inserting the armature thereon, and then securing the U-shaped frame member to the wail 22 by means of the screws 2S). For holding the coils in position upon the polepieces and preventing their slipping inwai-dy or becoming accidently displaced, so as to contact with the armature, I provide suitable spring clips 42 which may extend across from one coil tothe other and may be held from inward movement by engaging with the pole-pieces.
Ilhe transverse member 28 of the motor frame is provided with a bridge 34 on its side away from the diaphragm, and the entire bridge is preferably integral with the motor trame. The two legs 33 and 35 o'tl the. bridge have alined openings substantially parallel to the transverse portion 2S of "the motor iframe, and within these openings are brushes 3G which are adjustable and are held in place in any suitable manner, as for instance by screws extending inwardly from the outer surface ot the transverse member of the bridge. The commutator is located between the two legs on the bridge, and is thus readily accessible from each side.
YIwo insniated wires 37 lead from the two coils to the outer ends of the two brushes and two insulated wires 38 lead from the coils through the opening 25 to terminals on the incl ined or conical wall 24. The terminals limnay be et any suitable character. I have shown bolts extending through insulated bushings and having loclc nuts at the outer f end for retaining the Wires.
The end of the armature shaft preferably fits within a socket in the plug 48 screwed into the bridge 34, intermediate of the ends of the iatter. 'This plug constitutes an adjustable thrust bearing, whereby the armature may bc 'forced endwise a limited distance toward the diaphragm to insure the proper contact ot the rotor with the diaphragm. At the opposite end ot the armature and between the latter and the transverse wall 22 I provide a leaf-spring 50 which normally tends to force the armature back into contact with thc thrust bearing. The specific vform of spring shown is a lcaf spring normally bowed and perforated at its center to receive the armature sha't't. The ends of the spring engage with the transverse wall and the central portion engages with a washer or collar on the armature shaft or on the armature. Upon assembling the horn, the spring will normally push the armature bach to such a position that the rotor will not properly contact with the wear-piece, but by means ol" the thrust bearing the armature and rotor are advanced until the proper engagement is secured and the armature is held between the spring and the thrust bearing. This avoids the necessity oi absolute accuracy in the forming or assembling of the parts and permits the taking up ot' wear on the rotor. The plug forming the thrust bearing may be held in place after adjusting, in any suitable manner, as for instance by a lock nut 4l. It preferably has an annular external groove communicating with an oil duct in the bridge as shown in Fig. 2. 'l' his groove communicates with the socket receiving the end of the armature shalt through a small passage as indicated in F ig. 1.
For lubricating the armature shaft at its opposite end I may provide a small duct 43, leading downwardly from the cylindrical wall 23 of the bearing of the armature shaft and upon the side toward the diaphragm, so as not to interfere with the armature or coils. For protecting the motor, I provide a thin casing 44 preferably of metal and preterably of cylindrical form. rlhe casing is shown as being` ot cl|pshape with thc open end slipping on to the cylindrical wall 2 and then held in place by suitable screws 45. The length oi this cylindrical wall determines the endwise sliding movement of the casing and the casing is preferably considerably smaller than the diaphragm, so that tlrc inclined wall serves not only to limit thex position ot the casing 44, but connects the, casing oiE small diameter to the diaphragm clamps ol larger diameter. The
easing 44 also preferably covers the upper end of the oil duct 43 so as to protect the latter from dust and dirt.
It will be noted that oy merely removing the twoscrews 45, the casing 44 may be taken oi and all ott` the parts of the motor will be exposed so that they may be adjusted, replaced or repaired without removing the motor from the horn. By extending the wires 38 from thc field coils through the opening 25 and mounting the terminals 46 on the inclined wall 24, it will be noted that the removal of the case 44 does not disturb the wiring connection to the motor and that the motor may be run and tested and its opffii eration noted with kthe casing removed. Any snita le means may be employed for supporting the horn, for instance a bracket e7 ivhich may be secured to the diaphragm casl ing by two of the bolts, which hold the diaphragm clamping portions in position, as shcwn'in Fig.1 4s I thus described my invention, what i claim as new and desire to protect by Letters Patent, is;
l. :in ahorn or sifrnaling device, the
r@ambinatioi'i of an elastic diaphragm, a
transverse member in the rear thereof, a speed electric motor secured to said member and having its armature shaft j ournaled irl/said member and presented endtvpise to said diaphragm, a rotor carriedby shaft for effecting vibration of said diaphragm toward ahd from said rotor, an adjustable thrust bearing for limiting the axial rearward movement of said shaft and said rotor under the reaction of diaphragm, and a bowed leaf spring disposed between the armature of said motor and the rear surface of said member for main- Vdiaphragm case, the armature shaft of said electric motor extending through said plain rear 'wall and presented endivise to the diaphragm, ari-actuator mounted upont said armature shaft and disposed within the diaphragm case, an adjustable end thrust bearing for said armature shaft for moving lthe sametovvard the diaphragm, and a spring mounted on said shaft and having its end portions supported by said diaphragm case and its intermediate portion bowed toward said end thrust bearing to normally hold the armature shaft the maximum adjusted distance from the diaphragm.
3. In a horn, a diaphragm, a diaphragm case having a substantially plain rear Wall, an electric motor at the rear of said diaphragm case, the armature shaft of said electric motor extending through said plain rear Wall and presented endvvise to the diaphragm, an actuator mounted upon said armature shaft and disposed Within the diaphragin case, an adjustable end thrust bearing for said armature shaft for moving the same toward the diaphragm, and a spring mounted on said shaft and having its end portions supported by said diaphragm case and its intermediate portion bowed toward said end thrust bearing to maintain the armature shaft in engagement with said thrust bearing throughout the range of normal adjustment and operation ofthe device.
4i. n a horn, a diaphragm, an electric motor at the rear of said diaphragm and having its armature shaft presented end- Wise to the diaphragm, a transverse wall between the armature of said motor and said diaphragm and through which said shaft extends, an actuator mounted upon saild armature shaft and disposed between said Wall and said diaphragm, an adjustable end thrustbearing for said armature shaft for moving the same toward the diaphragm and a spring mounted on said shaft and having its end portions supported by said Wall and an intermediate portion bowed toward said thrust bearing to normally hold the armature shaft the maximum distance from the diaphragm.
Signed at Newark in the county of Essex and State of New Jersey this 8rd day of January A. D. 1914.
DUNCAN A. MCCONNELL.
US81080114A 1914-01-07 1914-01-07 Diaphragm-horn. Expired - Lifetime US1228226A (en)

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