US1335978A - Recording-telephone - Google Patents

Recording-telephone Download PDF

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US1335978A
US1335978A US64895A US6489515A US1335978A US 1335978 A US1335978 A US 1335978A US 64895 A US64895 A US 64895A US 6489515 A US6489515 A US 6489515A US 1335978 A US1335978 A US 1335978A
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frame
diaphragm
stylus
magnet
core
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John F Malthaner
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M1/00Substation equipment, e.g. for use by subscribers
    • H04M1/64Automatic arrangements for answering calls; Automatic arrangements for recording messages for absent subscribers; Arrangements for recording conversations

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  • My invention relates to a, dictating and recording telephone mechanism ,and more particularly to a device of that character which may be of convenient size and weight for use on an office desk or similar place.
  • the mechanism is designed so-thatit may be used to receive direct dictation for phonographic records and also to receive telephone messages from the ordinary telephone receiver'to record the same.
  • Figure 1 1s a vertical cross sectlonal view of an improvedrecorder arranged to fit a standard reoorder'frame, such as an Edison spectacle frame;
  • Fig. 2 is a bottom plan view of the same;
  • Fig. 3 is, a horizontal cross section of the same on the line 3-3 of Fig. 1;
  • Fig. 4 is a plan view .of the counter-weight and supporting spring for the recorder frame
  • Figs. 5 and 6 are perspective views of the improved diaphragms or reeds designed for use1 on "the recorder shown in Figs. 1 to 3; an
  • Fig. 7 is a diagram showing the circuit connections of the mechanism. embodying the invention.
  • the apparatus comprises a telephone transmitter T of the-usual or any preferred designcand 'isprovided with a mouth-piece M and with a bracket B upon which the ordinary'type of receiver B may be supported.
  • the mouthpiece M consists of a long tube 0 enin into the transmitter casing and ,a brancfi duct D extends from the mouth-piece tube upwardly and opens at the center ofthe top of the bracket B to register with theopenj ing in the ordinary receiver R.
  • the transmitter Tis connected by a wire 10 to a point intermediate the ends of the battery 11, and
  • wire 25 connectsthe divided circuit to the winding 26 of a magnetic recorder, the other end of the winding 26 being connected by a wire 27 to one side of the battery 11.
  • the phonographic record medium is indicated diagrammatically at P and is in the form of a cylinder adapted to be engaged by a stylus 31 carried by a diaphragm 32 which is mounted at its opposite ends on the frame33.
  • the frame 33 carries an electro-magnet which consists of a core 34 and a winding 26 surrounding the core.
  • the ele'ctro-magnet is designed to vibrate the diaphragm 32 and stylus 31 and the winding 26-thereof is connected to the,
  • the magnet supporting frame 33 consists of a member of magnetic material bent so as to provide a top.
  • the pin 352 extends through the arms 351 and 336 and forms the pivot upon which .the frame 33 rocks.
  • the cylindrical casing 35 is threaded at its upper end and closed by a screw cap 36 and near its lower end it has a circular projection 353 which provides a shoulder to support the casing in-the usual spectacle frame in a standard Edison phonograph.
  • the walls of the casing 35 are bored to receive insulating bushings, 354 which carry the terminal posts 37-by means of which the. circuit 'wires 25 and 27 are connected to the magnet winding 26, mounted on the frame 33.
  • the top portion of the frame 33 extends upwardly into the casing 35' and the horizontal portions 334 and 335 are located'below the bottom edge of the casing.
  • the outer end of the frame 33 is yieldingly supported by means of a counter weight consisting of a solid block of metal 38 which is pivotally supported at the diametrically opposite sides of the casing by the pivot screws 381.
  • a spring plate 39 is fastened to the under side of the block 38 and has the hook 391 at the outer end thereof to receive a-rod 40 which connects the plate 39 to a hook 401 near the outer end of the frame 33. In order to adjust the weight 38 and its.
  • counter balancing effect I provide a screw 41 which fits a threaded lug 382 on the top side of the weight 38 and which may be set in any adjusted posi- It will be obvious that by turning the screw 41 the amount of counter-balancing effect exerted by the weight 38 'may be varied and thereby the outer end of the frame 33 may be raised or lowered.
  • the core 34 of the electro-magnet is secured to the inner side of the top 331 of the frame 33 by a screw 341 which draws the core into close contact with the frame to diminish the magnetic leakage at the joint.
  • the opposite end of the core 42 extends to a point substantially opposite the center of a diaphragm or reed 32 which consists of 'a flexible, narrow strip of magnetic material.
  • the reed 32 is secured at its opposite ends by screws 321 to theunder sides of the parts 334 and 335 of the frame 33.
  • arms 334 and 335- have their bottom. faces cut away for part of, the length thereof as at-322 and 323 to leave shoulders on the under sides of thosearms which support the reed 32a slight distance from the arms leaving the narrow air gaps 322 and 323 between the diaphragm and a portion of the frame.
  • the magnetic flux flowing through the pole pieces 332 and 333 will in part flow across or jump the small air gaps 322 and 323 instead of travcling to the shoulders supporting the endsof the reed.
  • the recorder herein shown is more eflicient than the one shown in my prior application above re ferred to.
  • a reed constructed of the same width from end to end is preferable.
  • a reed 45 of this construction and approximately at its center is mounted a square soft iron disk 46 which is held in place by integral clips 47 and on its under side it has a shoulder for supporting the sapphire or stylus in the same way as shown in Fig. 1.
  • a .felt washer 48 is also employed and surrounds the lower end of the o magnet core, similar to the washer 44.
  • the soft iron sapphire mounting is advantageous because it loads the center or approximate center of the reed and eliminates metallic sounds. .
  • the amplitude of the reed is also increased and I am able to use a reed of larger gage mild steel than in the device described in my former application.
  • By loading the center of the reed a hammer effect is obtained which is desirable in this apparatus.
  • the arrangement affords a greater mass of iron for the magnetic flux in proximity to the core of the magnet and bemg of greater diameter than the core of the magnet it eliminates over-saturation-of the reed or dissipation of magnetic flux at the point opposite the core of the magnet.
  • a .phonographic recorder comprising a diaphragm of magnetic material, a stylus associated with said diaphragm, an electro- -magnet having a soft iron'core, one end of said core bein in closed magnetic circuit with said diap ragm, the otherend ofsaid core being disposed substantially opposite the center of said diaphragm and separated therefrom by a narrow air gap and adapted to vibrate the diaphragm and stylus when the electromagnet is energized.
  • a phonographic recorder comprising a diaphragm of magnetic material, a soft iron disk mounted on the under side of said diaphragm, a stylus mounted on the under side of said disk, and an electro-magnet- 1ocatedopposite the upper side'of said dia- 20 'phragm and adapted to vibrate said diaphragm, disk and stylus.
  • a phonographic recorder comprising a frame, a diaphragm of magnetic. material secured to said frame and having a part sep-- 'arated from said frame by a narrow air gap, a stylus carried on one side of said diaphragm, and an electro-magnet on the'frame opposite said stylus for vibrating said diaphragm and stylus, said magnet being secured to the frame with one end in closed magnetic circuit with said'frame.
  • a phonographic. recorder comprising a frame, a diaphragm in the form of an elongated member of magnetic material secured to opposite sides of said frame, a soft iron disk mounted on the outer'side of said diaphragm near the center thereof, a lug on said disk, a stylus mounted/on said lug, and
  • anelectro-magnet carried by saidframe and 40 adapted to vibrate said diaphragm, disk and st us.
  • a frame comprising a U- shaped device having armsat opposite sides thereof, a diaphragmattached to the arms of said frame and comprising a reed of magnetic material, a soft iron mounting secured to the rec at its center, a stylus attached to the-outer side of said mounting, an electro- 0 magnet secured to said frame and arranged to vibrate said reed and the stylus thereon.
  • a diaphragm comprising a strip of flexible magnetic material, a phonographic stylus, a soft iron disk intermediate the ends of said diaphragm for connecting said stylus to the diaphragm, a frame for supporting said diaphragm at the ends thereof, and an electro-magnet mountedgon the frame and disposed opposite the center of said diaphragmand adapted to vibrate the latter and the stylus thereon.
  • 114A phonographic recorder comprising a diaphragmofmagnetic material, a stylus associated with said diaphragm, an electromagnet-having one pole extended to engage the perimeter of said diaphragm, the opposite pole of said magnet being disposed subs 125 ciated with said diaphragm, an electromag net having a soft iron core one end of which is in closed magnetic relation with said dia phragm, the opposite end of said core being disposed substantially opposite the center'of' said diaphragm and separated therefrom by a narrow air gap which permits the passage of magnetic flux to vibrate the diaphragm and the stylus associated therewith.
  • a phonographic recorder comprising an electromagnethaving a soft iron core, a soft iron armature, a stylus associated with I said armature, one end of said core having a closed magnetic circuit with said armature, the other end of said core being separated from said armature by a narrow air gap which permits an open passage for magnetic flux whereby changes in magnetic flux in said core are adapted to actuate said armature and the stylus associated thergwith when said electromagnet is energize v l4
  • said stylus a soft iron disk carrying said stylus and secured to the othef side of said diaphragm near the center, said electro-magnet having a core disposed opposite the center of said diaphragm, and a'was'her surrounding the end of said core and disposed between the magnet and said diaphragm, said yielding supporting means including a pivoted balance Weight and means for changing the center of gravity of the Weight relative to itspivots;

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  • Engineering & Computer Science (AREA)
  • Signal Processing (AREA)
  • Reciprocating, Oscillating Or Vibrating Motors (AREA)

Description

. J. F. MALTHANER.
v RECORDING TELEPHONE.
APPLICATION FILED DEC. 3. 1915. I I 1,335,97 Patented Apr. 6, 192D I To all whom it may camera:
I ATENT; orrrn.
JOHNF. MALTEANER, or ATLANTA, GEORGIA.
RECORDING-TELEPHONE.
Lseaeve.
' Specificatin of Letters Patent.
Patented Apr. 6., 1920.
Original application filed August '3, 1915, Serial No. 43,471. Patented January 7, 1919, No. 1,290,621.
fIDivided and this application. filed December 3, 1915. Serial No. 64,895.
Be it known that 1 JOHN F: MALTHANER, a citizen of the United States, and resident of Atlanta', county of Dekalb, State of Geor gia, have invented certain new and useful lmprovementsin Recording-Telephones, of
.which the following-is a specification.
My invention relates to a, dictating and recording telephone mechanism ,and more particularly to a device of that character which may be of convenient size and weight for use on an office desk or similar place. The mechanism is designed so-thatit may be used to receive direct dictation for phonographic records and also to receive telephone messages from the ordinary telephone receiver'to record the same.
This application constitutes an improvement on part of the mechanism shown and described in my pendin application Serial No. 876,864,filedDecem er 12, 1914, and a division of my application No. 43,471, filed August 3, 1915.
The objects and novel features of the invention will be apparent from the following description taken in connection with the drawing, in which,
Figure 1 1s a vertical cross sectlonal view of an improvedrecorder arranged to fit a standard reoorder'frame, such as an Edison spectacle frame;
Fig. 2 is a bottom plan view of the same; Fig. 3 is, a horizontal cross section of the same on the line 3-3 of Fig. 1;
Fig. 4 is a plan view .of the counter-weight and supporting spring for the recorder frame; Figs. 5 and 6 are perspective views of the improved diaphragms or reeds designed for use1 on "the recorder shown in Figs. 1 to 3; an
Fig. 7 is a diagram showing the circuit connections of the mechanism. embodying the invention.
Referring to Fig. 7, the general arrangement of the apparatus is shown in diagram and is described in detail in .the' parent ap- Q plication above referred to. In. general the apparatus comprises a telephone transmitter T of the-usual or any preferred designcand 'isprovided with a mouth-piece M and with a bracket B upon which the ordinary'type of receiver B may be supported. The mouthpiece M consists of a long tube 0 enin into the transmitter casing and ,a brancfi duct D extends from the mouth-piece tube upwardly and opens at the center ofthe top of the bracket B to register with theopenj ing in the ordinary receiver R. The transmitter Tis connected by a wire 10 to a point intermediate the ends of the battery 11, and
by a wire 12 to the primary winding 13 of an induction coil I. The other end of the induction will is connected by a wire 14 to a contact spring 15. The operation of the spring 15 and the flow of current through the induotionwoil I may be controlled by depressing a button 18 connected .to a con- 23 and the receiver 24, the condenser 23 and receiver 24 "being connected in series. The
wire 25 connectsthe divided circuit to the winding 26 of a magnetic recorder, the other end of the winding 26 being connected by a wire 27 to one side of the battery 11. A lamp 28 connected bywires 29 and 30 to the wires 10 and 14, respectively, serves as a signal to indicate when the button 18 is depressed as the lamp will be lighted when the circuits are closed at the key 18'.
The phonographic record medium is indicated diagrammatically at P and is in the form of a cylinder adapted to be engaged by a stylus 31 carried by a diaphragm 32 which is mounted at its opposite ends on the frame33.
Referring to Figs. '1, 2 and 3', the frame 33 carries an electro-magnet which consists of a core 34 and a winding 26 surrounding the core. The ele'ctro-magnet is designed to vibrate the diaphragm 32 and stylus 31 and the winding 26-thereof is connected to the,
wires 25 and 27, as heretofore set forth, and is therefore-in circuit with the telephone instruments T and 24. The magnet supporting frame 33 consists of a member of magnetic material bent so as to provide a top.
portion 331 and two downwardly extending parts the parts 332 and 333, are two oppositely 332 and 333. At the lower ends of outwardly extending arms 334 and 335, ex-
tending at right angles to the'arms 332 and 333, respect1vely,t;he arm 335 having a bear tion by a nut 411.
35'. I The pin 352 extends through the arms 351 and 336 and forms the pivot upon which .the frame 33 rocks.
The cylindrical casing 35 is threaded at its upper end and closed by a screw cap 36 and near its lower end it has a circular projection 353 which provides a shoulder to support the casing in-the usual spectacle frame in a standard Edison phonograph. The walls of the casing 35 are bored to receive insulating bushings, 354 which carry the terminal posts 37-by means of which the. circuit ' wires 25 and 27 are connected to the magnet winding 26, mounted on the frame 33. The top portion of the frame 33 extends upwardly into the casing 35' and the horizontal portions 334 and 335 are located'below the bottom edge of the casing.
The outer end of the frame 33 is yieldingly supported by means of a counter weight consisting of a solid block of metal 38 which is pivotally supported at the diametrically opposite sides of the casing by the pivot screws 381. A spring plate 39 is fastened to the under side of the block 38 and has the hook 391 at the outer end thereof to receive a-rod 40 which connects the plate 39 to a hook 401 near the outer end of the frame 33. In order to adjust the weight 38 and its. counter balancing effect I provide a screw 41 which fits a threaded lug 382 on the top side of the weight 38 and which may be set in any adjusted posi- It will be obvious that by turning the screw 41 the amount of counter-balancing effect exerted by the weight 38 'may be varied and thereby the outer end of the frame 33 may be raised or lowered.
The core 34 of the electro-magnet is secured to the inner side of the top 331 of the frame 33 by a screw 341 which draws the core into close contact with the frame to diminish the magnetic leakage at the joint. The opposite end of the core 42 extends to a point substantially opposite the center of a diaphragm or reed 32 which consists of 'a flexible, narrow strip of magnetic material. The reed 32 is secured at its opposite ends by screws 321 to theunder sides of the parts 334 and 335 of the frame 33. The
. arms 334 and 335- have their bottom. faces cut away for part of, the length thereof as at-322 and 323 to leave shoulders on the under sides of thosearms which support the reed 32a slight distance from the arms leaving the narrow air gaps 322 and 323 between the diaphragm and a portion of the frame. By this arrangement the magnetic flux flowing through the pole pieces 332 and 333 will in part flow across or jump the small air gaps 322 and 323 instead of travcling to the shoulders supporting the endsof the reed. In this particular the recorder herein shown is more eflicient than the one shown in my prior application above re ferred to.
)The construction of thereed or diaphragm used may be either the one shown in Fig. 5 or the one shown in Fig. 6,. the one shown in Fig. 5 being shown in position on the provided with integrally bent lugs 432,-
which engage the opposite sides of the disk 43 and hold it in position.. In order to dampen the vibrations and prevent cuttings and other fpreign substances from getting between the end of the core 34 and the diaphragm 32, I employ a felt washer 44 whlch surrounds the end of the core and fits between the magnet and diaphragm.
I find that for some purposes a reed constructed of the same width from end to end is preferable. In Fig. 6 I have shown a reed 45 of this construction and approximately at its center is mounted a square soft iron disk 46 which is held in place by integral clips 47 and on its under side it has a shoulder for supporting the sapphire or stylus in the same way as shown in Fig. 1. In this form of reed a .felt washer 48 is also employed and surrounds the lower end of the o magnet core, similar to the washer 44.
The soft iron sapphire mounting is advantageous because it loads the center or approximate center of the reed and eliminates metallic sounds. .The amplitude of the reed is also increased and I am able to use a reed of larger gage mild steel than in the device described in my former application. By loading the center of the reed a hammer effect is obtained which is desirable in this apparatus. Primarily, howeyer, the arrangement affords a greater mass of iron for the magnetic flux in proximity to the core of the magnet and bemg of greater diameter than the core of the magnet it eliminates over-saturation-of the reed or dissipation of magnetic flux at the point opposite the core of the magnet.
While I have shown and described the device in detail I do not wish to be limited to the exact construction as set forth. Various modifications may be made, therein without departing from the 'spirit of the invention.
Having thus described the. invention, what is claimed and desired to be secured by Letters Patent is: Q
:1. A .phonographic recorder comprising a diaphragm of magnetic material, a stylus associated with said diaphragm, an electro- -magnet having a soft iron'core, one end of said core bein in closed magnetic circuit with said diap ragm, the otherend ofsaid core being disposed substantially opposite the center of said diaphragm and separated therefrom by a narrow air gap and adapted to vibrate the diaphragm and stylus when the electromagnet is energized.
2. A phonographic recorder comprising a diaphragm of magnetic material, a soft iron disk mounted on the under side of said diaphragm, a stylus mounted on the under side of said disk, and an electro-magnet- 1ocatedopposite the upper side'of said dia- 20 'phragm and adapted to vibrate said diaphragm, disk and stylus.
3. A phonographic recorder comprising a frame, a diaphragm of magnetic. material secured to said frame and having a part sep-- 'arated from said frame by a narrow air gap, a stylus carried on one side of said diaphragm, and an electro-magnet on the'frame opposite said stylus for vibrating said diaphragm and stylus, said magnet being secured to the frame with one end in closed magnetic circuit with said'frame.
4. A phonographic. recorder comprising a frame, a diaphragm in the form of an elongated member of magnetic material secured to opposite sides of said frame, a soft iron disk mounted on the outer'side of said diaphragm near the center thereof, a lug on said disk, a stylus mounted/on said lug, and
' anelectro-magnet carried by saidframe and 40 adapted to vibrate said diaphragm, disk and st us.
5. In an apparatus of the class described, the combination of a frame comprising a U- shaped device having armsat opposite sides thereof, a diaphragmattached to the arms of said frame and comprising a reed of magnetic material, a soft iron mounting secured to the rec at its center, a stylus attached to the-outer side of said mounting, an electro- 0 magnet secured to said frame and arranged to vibrate said reed and the stylus thereon.
' 6. In an apparatusof the class described,
the combination of a stylus, a diaphragm, a
frame carrying said stylus and diaphragm, said frame having a portion thereof spaced from said diaphragm by a relatively small airgap to permit flux to pass from the frame to the diaphragm intermediate the ends of theJatter, and an electro-magnet secured to said frame and having its core dispdsed-sub- 1 stantially' opposite-the center of said diaphragm and adapted to. vibrate'the latter arfdthe stylus thereon.-
7 In; an apparatus of the class described,
the combination of a frame, means for piv ter of said diaphragm, and a washer surrounding the end ofsaid core and disposed between the magnet and said diaphragm.
8. In an apparatus of the class described, the combination of a diaphragm comprising a strip of flexible magnetic material, a phonographic stylus, a soft iron disk intermediate the ends of said diaphragm for connecting said stylus to the diaphragm, a frame for supporting said diaphragm at the ends thereof, and an electro-magnet mountedgon the frame and disposed opposite the center of said diaphragmand adapted to vibrate the latter and the stylus thereon.
9. In an apparatus of the class described, the combination of an inverted U-shaped frame having laterally extending arms at the bottom' thereof, said armshaving promi-' nenceson the bottomfac'es thereof, a diaphragm in the form of a reed attached to said prominences: on the frame and spaced a slight distance from said arms by a narrow air gap which permits the passage of flux fromthe frame to-the reed, a stylus on the. outer-side of said diaphragm, and an electro-magnet secured to said frame between 1 0 the limbs thereof. I
10, In an apparatus of the class described,
the combination of a casing adapted to fit a standard'Edison spectacle frame, an inverted U-shaped supporting frame pivoted on and extending into said casing, the limbs of A said U-shaped frame having laterally ex-' tending armsat the bottoms thereof provided-with prominences on the bottom faces thereof, a diaphragm-in the form of a flat narrdw reed attached to said prominences on the'frame and spa ed from the remaining portion of the bottom faces of said arms by a narrow air gap. which permits the passage of flux from the'limbs of the frame directly across thegap to said diaphragm, a
soft iron stylus mounting on the outer side of said diaphragm near the center thereof, a stylus carried by said mounting, and an electro-magnet secured between thelimbs of said frameand having the core thereof ex-' tending close to ;the center of ,said diaphra'gm on theside opposite thereof from said mounting. 7 114A phonographic recordercomprising a diaphragmofmagnetic material, a stylus associated with said diaphragm, an electromagnet-having one pole extended to engage the perimeter of said diaphragm, the opposite pole of said magnet being disposed subs 125 ciated with said diaphragm, an electromag net having a soft iron core one end of which is in closed magnetic relation with said dia phragm, the opposite end of said core being disposed substantially opposite the center'of' said diaphragm and separated therefrom by a narrow air gap which permits the passage of magnetic flux to vibrate the diaphragm and the stylus associated therewith.
13. A phonographic recorder comprising an electromagnethaving a soft iron core, a soft iron armature, a stylus associated with I said armature, one end of said core having a closed magnetic circuit with said arma ture, the other end of said core being separated from said armature by a narrow air gap which permits an open passage for magnetic flux whereby changes in magnetic flux in said core are adapted to actuate said armature and the stylus associated thergwith when said electromagnet is energize v l4 In an apparatus of the class described, the combination of a frame, means for pivotally supporting the frame at one side, means for yieldingly supporting the frame at the opposite side, an electro-magnet secured to the frame between said supporting means, a diaphragm secured to the frame, a'
stylus, a soft iron disk carrying said stylus and secured to the othef side of said diaphragm near the center, said electro-magnet having a core disposed opposite the center of said diaphragm, and a'was'her surrounding the end of said core and disposed between the magnet and said diaphragm, said yielding supporting means including a pivoted balance Weight and means for changing the center of gravity of the Weight relative to itspivots; i
In testimony whereof I affix my signature.
JOHN F. MALTHANER.
US64895A 1915-08-03 1915-12-03 Recording-telephone Expired - Lifetime US1335978A (en)

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