US1699786A - Pressure-distributing device - Google Patents

Pressure-distributing device Download PDF

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US1699786A
US1699786A US211065A US21106527A US1699786A US 1699786 A US1699786 A US 1699786A US 211065 A US211065 A US 211065A US 21106527 A US21106527 A US 21106527A US 1699786 A US1699786 A US 1699786A
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United States
Prior art keywords
diaphragm
pressure
corrugations
radial
triangular
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Expired - Lifetime
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US211065A
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Thaddeus R Goldsborough
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CBS Corp
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Westinghouse Electric and Manufacturing Co
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Priority to NL25055D priority Critical patent/NL25055C/xx
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Priority to US211065A priority patent/US1699786A/en
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R7/00Diaphragms for electromechanical transducers; Cones
    • H04R7/02Diaphragms for electromechanical transducers; Cones characterised by the construction
    • H04R7/12Non-planar diaphragms or cones
    • H04R7/14Non-planar diaphragms or cones corrugated, pleated or ribbed

Definitions

  • 'rimnnnus a eonnsnonouox, or wmxmsnuae, rnnnsxnvanu, .assrexoa 'ro wnsrmenousn mo-rarc & MANUFACTURING comm, a ooaronarron or rmsnvam.
  • I M invention relates to pressure-distribut- Another object of m invention is to proing evices, and it has particular relation to vide an improved diap ragm of the pleated 'diaphragms for telephone receivers, loud type in which none of the elements thereof are speakers, phonographs, and the like. in objectionable vibratory contact with each With only few exceptions, devices inother when the diaphragm is actuated.
  • Another object of my invention is to prosort of vibratile diaphragms, either of small vide a diaphragm of the pleated type in dimensions associated with horns, or of relawhich driving forces are carried from the tively great areas which directly act upon the center to the periphery thereof along salient 10 air without the intervention of horns or angles formed by the intersections of the analogous devices. faces of the pleats.
  • Diaphragms of the latter type have been Another object of m invention is to pro made of many different materials, such as vide a corrugated diaphragm of novel shape paper, laminated wood, balsa-wood, spun which, when in vibration, is damped to some 5 aluminum, and the like, and have assumed extent by radial air-currents which are con- 66 many different forms varying from flat to strained to flow between the individual corconical, in the effort to secure the greatest rugations. rigidity commensurate with the mass thereof.
  • Another object of my invention is to pro- It has also been proposed to construct a vide a novel configuration for a diaphragm diaphragm ofa pleated sheet of paper, by or other object stamped, embossed, or mol arranging the pleats, or corrugations radifrom relatively thin material, that will have ally, and by so distorting them that the diamaximum stifl'ness relative to the mass hragm v'aries progressively, in flexibility, thereof.- mm a stiff central portion toward the pe- According to one modification of my in- 25 riphery thereof.
  • Pleated 'diaphragms are vention, I attain the aforementioned objects 76 exemplified by the patent to Lumiere, No.
  • FIG. 1 is a rear elevational view of a pleated diaphragm constructed according to a preferred embodiment of my invention
  • Fig. 2 is a cross-sectional view taken along a line corresponding to the line IIII of Fig. 1,
  • Fig. a line corresponding to Fig. 1,
  • Fig. 4 is a front elevational view
  • Fig. 5 is a view of a portion of paper or parchment that has been scored preparatory to being folded according to my invention.
  • a plu- 3 is a cross-sectional View taken along the line III--III of ra ity'of approximately trough-shaped cor-' from a central hub 2, P
  • rugations 1 radiating the corrugations being of alternately disposed ribs 3 and depressions 4, the ribs on one side of the diaphragm corresponding to the depressions on the other side thereof.
  • each rib behaves as though it were a reinforced girder, or beam, and does not buckle when forces are applied. to either end there- 'of.
  • the diaphragm as a whole, therefore, can not buckle under forces applied at the center if the peripheral ends of the separate ribs are prevented from spreading.
  • the spreading of the ribs is prevented by atfixing of a mounting rim 13, preferably made of than the material from which the'diaphragm itself is made, to the elements 6.
  • a diaphragm having the superficial configuration just described may be formed from a single rectangular sheet of paper, parchment, or the like, by folding or leating it in the manner indicated in Fig.
  • the length of the strip of material before scoring and folding should be approxireason of the merging mately twice the circumference of the fin- I ished diaphragm, while the width thereof should be substantially equal to the radius of the finished diaphragm.
  • the lines 15, 16' and 17 represent creases presenting salient angles to the observer when the sheet is viewed from above, and the lines 18, 19, 20 and 21 represent re-ent-rant an 'les when viewed from the same position.
  • mall triangular portions 22 of the material, bounded by the lines 23 and 24: and the edge of the strip, are then preferably removed, and the ends of the strip are then brought together and secured.
  • the diaphragm presents the appearance of a cylinder having fluted sides.
  • the perimeter of one end of the fluted cylinder is next ressed inwardly toward the axis thereof, and then downwardly along the axis, forcing the material to assume a relatively fiat circular shape wherein the fluted elements or ribs lie radially of the axis of the cylinder,
  • Small Washers 27 may be slipped over each.
  • the exact length of the scored lines 15, 16, 18 and 20 may be left largely to the judgment of the manufacturer, although I have found it preferable to make them equal to each other.
  • a diaphragm constructed according to my invention has many advantages over pleated diaphragms known to the prior art. Perhaps the most pronounced advantage lies in the fact that, even when made from extremely light and flexible material, it assumes a configuration which gives it sufiicient rigidity to prevent flexing when it is suspended from a flexible mounting annulus and subjected 'to driving forces applied at the hub. Each element of the radial corrugations is so braced that it is prevented from flexing, and
  • the primary ob'ect of my invention is to provide a metho whereby an extremely rigid diaphragm ma be made by scoring and folding a single s eet of flexible material in a novel manner
  • my invention in so far as the configuration of the finished diaphragm is concerned, is equally applicable to diaphragms that are constructed by embossing, stamping or molding.
  • the peculiar manner in which the individual corrugations are terminated at their peripheral ends adds materially to the stren th of the finished product, and may very a vantageously be utilized in the fcrmlng of bearing members for foundations, or for devices intended to distribute stresses and strains over material.
  • a pressure-distributing device having a pluralit of radial corrugations the projections 0 which, on a plane parallel to said device, are quadrilaterals.
  • a pressure-distributing device having a pluralit of radial corrugations the projections 0 which, on a plane parallel to said device, are quadrilaterals, the peripheral angles of said quadrilaterals being separated by substantially triangular figures.
  • a pressure-distnbutingdevice having a a mass of semi-solid the peripheral e pro ection of upon a radial plane being chisel-shaped, the points of said chisel being periphera 5.
  • a pressure-distributmgvdevice having a plurality of radial corrugations ada ted to transmit force from the center of sai device to the periphery thereof through beamaction, the radial edges of said corrugations on one side of said device merging into radially extending edges lying at an an le to said first-mentioned e ges, and the ra ial edges of ad'acent corrugations on the other side of said evice merging into radially extending and approximately triangular-shaped surfaces lying at an angle to said radial edges.
  • a pressure-distributing device having a plurality of radial corrugations, the peripheral terminations of said corrugations simulating triangular yramids.
  • a pressure-distributing device having a pluralit of radial corrugations, said corrugations being braced a ainst deformation.
  • a pressure-distri uting device havin a plurality of radial corrugations, the perip eral terminations of said corru ations simulating triangular pyramids an the peripherally-lying apices of said pyramids being separated by triangular integral elements.
  • a pressure-distributing device having a plurality of radial corrugations, the peripheral terminations of said corrugations simulating triangular pyramids an the peripherally-lyin apices of said pyramids being separated y triangular integral elements lying approximately tangential to a conical surface.
  • a pressure-distributing device having a plurality of radial corrugatlons, the pen heral terminations of said corru ations being spaced by integral triangular e ements lyiu in the surface of a conical figure'the apex 0 which is positioned in a line perpendicular to a plane defined by the peripheral sides of any two of said triangular elements.

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  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Diaphragms For Electromechanical Transducers (AREA)

Description

Jan. 22, 1929- T. R. GOLDSBOROUGH PRESSURE DISTRIBUTING DEVICE Filed Aug. 6, 1927 ATTORNEY Patented Jan. 22, 1929. a 1,699,786
UNITED STATES PATENT OFFICE.
'rimnnnus a, eonnsnonouox, or wmxmsnuae, rnnnsxnvanu, .assrexoa 'ro wnsrmenousn mo-rarc & MANUFACTURING comm, a ooaronarron or rmsnvam.
' .rnnssmms'rmu'rme mwrcn.
a lication fled August a, 1927. gain in. 211,005.
I M invention relates to pressure-distribut- Another object of m invention is to proing evices, and it has particular relation to vide an improved diap ragm of the pleated 'diaphragms for telephone receivers, loud type in which none of the elements thereof are speakers, phonographs, and the like. in objectionable vibratory contact with each With only few exceptions, devices inother when the diaphragm is actuated. tended for sound reproduction embody some Another object of my invention is to prosort of vibratile diaphragms, either of small vide a diaphragm of the pleated type in dimensions associated with horns, or of relawhich driving forces are carried from the tively great areas which directly act upon the center to the periphery thereof along salient 10 air without the intervention of horns or angles formed by the intersections of the analogous devices. faces of the pleats.
Diaphragms of the latter type have been Another object of m invention is to pro made of many different materials, such as vide a corrugated diaphragm of novel shape paper, laminated wood, balsa-wood, spun which, when in vibration, is damped to some 5 aluminum, and the like, and have assumed extent by radial air-currents which are con- 66 many different forms varying from flat to strained to flow between the individual corconical, in the effort to secure the greatest rugations. rigidity commensurate with the mass thereof. Another object of my invention is to pro- It has also been proposed to construct a vide a novel configuration for a diaphragm diaphragm ofa pleated sheet of paper, by or other object stamped, embossed, or mol arranging the pleats, or corrugations radifrom relatively thin material, that will have ally, and by so distorting them that the diamaximum stifl'ness relative to the mass hragm v'aries progressively, in flexibility, thereof.- mm a stiff central portion toward the pe- According to one modification of my in- 25 riphery thereof. Pleated 'diaphragms are vention, I attain the aforementioned objects 76 exemplified by the patent to Lumiere, No. b so modifying the peripheral contour of a 1,036,526, and it is to them that the present pleated diaphragm made from a folded and inventionparticularl relates. scored portion of paper, parchment or Pleated paper diap ragms made according analogous material that each individual corto the teachings of the Lumiere patent are rugat-ion is capable of transmitting force 80 uite satisfactory when the power input to from the center of the diaphragmto the cirt e actuating means therefor is kept low, but cumference thereof through beam-action, and they are decidedly prone to rattle and to is prevented from flexing by a plurality of radiate buzzing sounds when forced to vispacing elements.
35 brate with large amplitudes. According to another form of my invenv I have established, by research and experition, a fiat circular portion of ductile material ment, that the unpleasant sounds 'accompanysuch as mild steel, aluminum, or the like, is ing the reproduction of speech and music by embossed or stamped into the same configurathe usual pleated paper diaphragm is primer tion that is given to a pleated paper diaphram 4 pally, if not entirely, caused by the exing when it is constructed according to the of the radial elements and by their vibratory method that will later bedescribed in detail. contact with one another when the diaphragm By reason of the fact that the rigidity of a is actuated. circular portion of material is vastly in- It is, accordingly, an object of my invencreased by being stamped, or corrugated, action to provide an improved diaphragm of cording to my invention, such stamped or as the pleated ty ethat is sufiiciently rigid from embossed articles may be very successfully the centerto t 1e periphery to ensure that the utilized as diaphragms, or as hearing memelements thereof will not flex when the diabers for building foundations, as strain-dis phragm is subjected to driving forces aptributing, or anchoring devices for maintainplied at the center. ing guy-wires and the like imbedded in the objects and advantages thereof, will best be understood frofn a consideration of the following description of a specific embodiment, taken in connection with the accompanying drawings, in which:
' side of the diaphragm and gives rise to a Figure 1 is a rear elevational view of a pleated diaphragm constructed according to a preferred embodiment of my invention,
Fig. 2 is a cross-sectional view taken along a line corresponding to the line IIII of Fig. 1,
Fig. a line corresponding to Fig. 1,
Fig. 4 is a front elevational view, and
Fig. 5 is a view of a portion of paper or parchment that has been scored preparatory to being folded according to my invention.
Referring specifically to Figs. 1, 2 and 3, in improved diaphragm comprises a plu- 3 is a cross-sectional View taken along the line III--III of ra ity'of approximately trough-shaped cor-' from a central hub 2, P
rugations 1 radiating the corrugations being of alternately disposed ribs 3 and depressions 4, the ribs on one side of the diaphragm corresponding to the depressions on the other side thereof. The ribs on both sides of the diaphragm, for the major portion of their radial length, lie in parallel planes, and diverge progressively from the hub toward the periphery.
As a point 5, lyin wardly from the perip side of the diaphragm the plane in which lie thereof and terminate in a plane parallel to thefirst mentioned plane and intermediate between it and the lane in which lie the major portions of tie ridges on the other The ridges, therefore, although not lying in a single plane, are substantially continuous from t e hub to the periphery. As shown in Fig. 4, the ridges on defined by a plurality a short distance inery, the ridges on one bend downward from the other side of the diaphragm merge into p a plurality of triangular elements 6, bounded by ridges 7 and 8, the peripheral boundaries 10 of which lie in the intermediate plane referred to above, and which are tangential to the-surface of an imaginary conical surf-ace 11 having its apex in the axis '12 of the diaphragm.
he merging gular elements 6 of the ridges into the trianis a result of the novel method of scoring and folding I have invented, diaphragm having very marked advantages over folded diaphragms known to the prior art.
' material slightly stiffer the maj or portions Forces originating in the electromagnetic actuating means (not shown) which may be coupled to the central hub by any suitable means, are transmi ted tot-he periphery of the diaphragm by what might be termed beam-action of each radial corru ation. In other words, by reason of the fact that the ribs on one side of the diaphragm extend in a substantially unbroken line from center to periphery, and, b of each rib on the otherside into two diverging ribs defining a triangular bracing element, each rib behaves as though it were a reinforced girder, or beam, and does not buckle when forces are applied. to either end there- 'of. The diaphragm, as a whole, therefore, can not buckle under forces applied at the center if the peripheral ends of the separate ribs are prevented from spreading. The spreading of the ribs is prevented by atfixing of a mounting rim 13, preferably made of than the material from which the'diaphragm itself is made, to the elements 6.
According to one method of practicing my invention, a diaphragm having the superficial configuration just described may be formed from a single rectangular sheet of paper, parchment, or the like, by folding or leating it in the manner indicated in Fig.
5. The length of the strip of material before scoring and folding should be approxireason of the merging mately twice the circumference of the fin- I ished diaphragm, while the width thereof should be substantially equal to the radius of the finished diaphragm.
Referring specifically to Fig. 5, the lines 15, 16' and 17 represent creases presenting salient angles to the observer when the sheet is viewed from above, and the lines 18, 19, 20 and 21 represent re-ent-rant an 'les when viewed from the same position. mall triangular portions 22 of the material, bounded by the lines 23 and 24: and the edge of the strip, are then preferably removed, and the ends of the strip are then brought together and secured.
At this stage of the forming operation, the diaphragm presents the appearance of a cylinder having fluted sides. The perimeter of one end of the fluted cylinder is next ressed inwardly toward the axis thereof, and then downwardly along the axis, forcing the material to assume a relatively fiat circular shape wherein the fluted elements or ribs lie radially of the axis of the cylinder,
the sides of said elements being closest to- I .phragm has now assumed t 3 respectivel are firmly cemeneted together. pluralit of radial corrugations the projec- The hub e ement 2 is next inserted into the tions 0 which, on a plane parallel to said small opening defined by the central ends of the ribs, and cemented in lace. The diae configuration clearly shown in Figs. 1 to 4 of the drawings.
Small Washers 27 may be slipped over each.
end of the hub, these washers eing cemented to the inner ends of the ribs, in order to better distribute theretothe actuating forces.
The exact length of the scored lines 15, 16, 18 and 20 may be left largely to the judgment of the manufacturer, although I have found it preferable to make them equal to each other.
I A diaphragm constructed according to my invention has many advantages over pleated diaphragms known to the prior art. Perhaps the most pronounced advantage lies in the fact that, even when made from extremely light and flexible material, it assumes a configuration which gives it sufiicient rigidity to prevent flexing when it is suspended from a flexible mounting annulus and subjected 'to driving forces applied at the hub. Each element of the radial corrugations is so braced that it is prevented from flexing, and
7 the tendency to nodal vibration substantially eliminated.
Although the primary ob'ect of my invention is to provide a metho whereby an extremely rigid diaphragm ma be made by scoring and folding a single s eet of flexible material in a novel manner, my invention, in so far as the configuration of the finished diaphragm is concerned, is equally applicable to diaphragms that are constructed by embossing, stamping or molding. The peculiar manner in which the individual corrugations are terminated at their peripheral ends adds materially to the stren th of the finished product, and may very a vantageously be utilized in the fcrmlng of bearing members for foundations, or for devices intended to distribute stresses and strains over material.
. Although I have shown only a single form of my invention, and have described only such form and a modification thereof not involving the folding of a strip of flat material, my invention is not to be restricted theret but is to be limited only by the prior art an the spirit of the appended claims.
I claim as my invention:
I 1. A pressure-distributing device having a pluralit of radial corrugations the projections 0 which, on a plane parallel to said device, are quadrilaterals.
2. A pressure-distributing device having a pluralit of radial corrugations the projections 0 which, on a plane parallel to said device, are quadrilaterals, the peripheral angles of said quadrilaterals being separated by substantially triangular figures.-
3. A pressure-distnbutingdevice having a a mass of semi-solid the peripheral e pro ection of upon a radial plane being chisel-shaped, the points of said chisel being periphera 5. A pressure-distributmgvdevice having a plurality of radial corrugations ada ted to transmit force from the center of sai device to the periphery thereof through beamaction, the radial edges of said corrugations on one side of said device merging into radially extending edges lying at an an le to said first-mentioned e ges, and the ra ial edges of ad'acent corrugations on the other side of said evice merging into radially extending and approximately triangular-shaped surfaces lying at an angle to said radial edges.
6. A pressure-distributing device having a plurality of radial corrugations, the peripheral terminations of said corrugations simulating triangular yramids.
7. A pressure-distributing device having a pluralit of radial corrugations, said corrugations being braced a ainst deformation.
8. A pressure-distri uting device havin a plurality of radial corrugations, the perip eral terminations of said corru ations simulating triangular pyramids an the peripherally-lying apices of said pyramids being separated by triangular integral elements.
9. A pressure-distributing device having a plurality of radial corrugations, the peripheral terminations of said corrugations simulating triangular pyramids an the peripherally-lyin apices of said pyramids being separated y triangular integral elements lying approximately tangential to a conical surface.
. -10. A pressure-distributing device having a plurality of radial corrugatlons, the pen heral terminations of said corru ations being spaced by integral triangular e ements lyiu in the surface of a conical figure'the apex 0 which is positioned in a line perpendicular to a plane defined by the peripheral sides of any two of said triangular elements.
.mergin into triangular elements.
12. e method of forming a relatively rigid pressure-distributin device from a rectangular sheet of flexib e material, which the pen
com rises pleating said sheet aflixing ing out re-entrant fold in the peripheral along lines perieular to the longest dimension thereof,
the ends of the sheet together, flattenthe cylinder so formed,
forming a termination of alternate pleats, and afiiXin%t0gether the edges of said folds, whereby t e peripheral terminations of said by approximately leats are spaced apart triangular elements that lie in a p ramidal surface towhich a mount 10 ing annu In testimony w scribed my name THADDEUS us maybe afiixed.
' I have hereunto subthis 29th day of July, 1927. R. GOLDSBOROUGH.
hereof,
US211065A 1927-08-06 1927-08-06 Pressure-distributing device Expired - Lifetime US1699786A (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4655316A (en) * 1985-03-13 1987-04-07 Jbl Incorporated Acoustic diaphragm
US4761817A (en) * 1986-01-27 1988-08-02 Harman International Industries, Incorporated Diaphragm structure for a transducer
US4881617A (en) * 1988-12-30 1989-11-21 Alexander Faraone Radially arcuated speaker cone
US5390254A (en) * 1991-01-17 1995-02-14 Adelman; Roger A. Hearing apparatus
US6026929A (en) * 1997-11-10 2000-02-22 Single Source Technology And Development, Inc. High frequency radially arcuated center speaker cone with variable thickness
WO2005015950A1 (en) * 2003-08-08 2005-02-17 Koninklijke Philips Electronics N.V. Loudspeaker with undulated membrane

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4655316A (en) * 1985-03-13 1987-04-07 Jbl Incorporated Acoustic diaphragm
US4761817A (en) * 1986-01-27 1988-08-02 Harman International Industries, Incorporated Diaphragm structure for a transducer
US4881617A (en) * 1988-12-30 1989-11-21 Alexander Faraone Radially arcuated speaker cone
US5390254A (en) * 1991-01-17 1995-02-14 Adelman; Roger A. Hearing apparatus
US6041129A (en) * 1991-01-17 2000-03-21 Adelman; Roger A. Hearing apparatus
US6026929A (en) * 1997-11-10 2000-02-22 Single Source Technology And Development, Inc. High frequency radially arcuated center speaker cone with variable thickness
WO2005015950A1 (en) * 2003-08-08 2005-02-17 Koninklijke Philips Electronics N.V. Loudspeaker with undulated membrane
CN1833464B (en) * 2003-08-08 2011-04-20 Pss比利时股份有限公司 Loudspeaker with undulated membrane

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