US565627A - Telephone-exchange system - Google Patents

Telephone-exchange system Download PDF

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US565627A
US565627A US565627DA US565627A US 565627 A US565627 A US 565627A US 565627D A US565627D A US 565627DA US 565627 A US565627 A US 565627A
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switchboard
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q1/00Details of selecting apparatus or arrangements
    • H04Q1/02Constructional details
    • H04Q1/14Distribution frames

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  • Figure 1 is a diagram showing the various circuits employed in my improved switchboard mechanism.
  • Fig. 2 is a vertical sectional view of my improved switchboard,with several of the circuits, however, omitted by reason of their not being presentable, at least without undesirable confusion, owing to the nature of the view.
  • Fig. 3 is an enlarged longitudinal sectional view of connected plugand-socket or spring-jack details;
  • Fig. 4 a broken perspective View showing modified means for a purpose the same as the means illustrated in Fig. 3;
  • Fig. 5, a broken sectional view showing a modified construction of a contact detail;
  • Fig. 6, aview in sectional elevation of a preferred construction of switch; and
  • Fig. 7 is a view, in the nature of a diagram, illustrating a modification.
  • A, Fig. 2 is the switchboard formed with a base A, from which rises the case A the front of which I prefer to divide into two panels A and A one for supporting the annunciators B and O, and the lower one for supporting the spring jacks or sockets D.
  • the ledge A of the base A which maybe formed of wood, are provided any desired number of rows of vertical openings r 7', each of which is surrounded by a perforated metal contactplate 0*, the perforation in which alines with the adjacent opening 7' or 1-, and the plate is hollowed out, as shown in Fig. 2, on its upper side about its perforation to afiord a seat for the end of a plug E.
  • the construction illustrated of the plug E comprises a metal rod 2, reduced toward one end, at the extremity of which it terminates in a rounded head if, the opposite end of the rod being expanded, as shown at and from this expanded portion'for some distance the rod is incased in insulating material 15 On the back ledge A of the 7 base A are provided binding-posts q for connection of the subscribers lines W WV,
  • each jack comprises a metal socket adapted to receive the reduced end of a plug, which is held'or steadied in place by a spring t extending forward from the rear end of the socket to engage the head 15 of the bar 25.
  • Behind the jacks D are metal (copper) bars F, supported in horizontal position one above the other, each extending across arow of the IOO correspond in number and relative situation,
  • these annunciators being of any suitable variety and construction, the variety shown 'bein g the ordinary magnet and drop.
  • Below the annunciators B is a row of ringing-off annunciators 0, similar to the others,though they should be wound to a higher resistance; and it is ordinarily necessary to provide but one of the annunciators O to, say, ten of the annunciators B, that being about the proportion of subscribers lines liable to be in use at any one time.
  • Each line-wire W of the system is connected by its insulated wire q, as shown in Fig. 1, with a plug E. From each contact-plate r there leads a wire to of the signaling-circuit through an annunciator B to ground.
  • G is a switch device, the details of which are hereinafter described, for controlling the three terminals 19,19, and p From the terminal 1) leads the wire 10 through an annunciator O to ground.
  • The'terminal p is at the end of the line Z02, which includes the generatorH and bell I of the operators call-circuit, and leads to ground.
  • the terminal 19 is at the end of the line-circuit formed with the wire 10 which I cause to lead to ground througha fine or secondary induction-coil 0, between a primary induction-coil and a repeating inductioncoil 0 the coil 0 being in the circuit 10 containing the local battery K and the transmitter T, and the induction-coil 0 being in the circuit 10 containing the receiver R.
  • the circuits containing the annunciators B are normally closed by the plates r and expandedends t of the plugs E being in contact, so that when a sub- 7 scriber sends a ringing-up signal over his line WVthe annunciator B on that line lets fall its drop, indicating to the operator at the exchange that the subscriber desires connection with another line.
  • the operator raises the plug E, forming the terminal of the line over which the call was received, thus (by pulling the insulated wires q through the plate r and separating them from the contact end of the plug) breaking the signalcircuit to on that line, and applies the plug N to the plug E, whereby the operators talking-circuit w is connectedwith the subscriber, and enables the operator to talk with the latter through the transmitter T and listen through the receiver R.
  • the operator Upon ascertaining the connection desired by the subscriber the operator applies the plug E of the subscriber to be called to anyspring-jack I) of a disengaged connectingrbarF, and by throwing the lever of the switch G to contact with the terminalp the generator-circuit 10 is closed, thereby enabling the operator to ring up the desiredgnumber.
  • the construction of the switch G I prefer to use is illustrated in Fig. 6. It comprises a plate on, of insulating material, from which depend the spring-terminals p and p and controlling-sprin gs m,which flank the switchlever Z, journaled on a plate Z, of insulating material, surmounting the plate m and coverin g the central opening therein,through which the switch-lever extends, and the controllingsprings m are held in place by the means for fastening the plate 1 to the plate m, a binding-post U being employed for connecting the wire to with one of the springs m and through the latter with the switch-lever with which the springpermanentlycontacts.
  • the switchlever Afterringing up the subscriber to, be called, the switchlever is released to resume its normal position of contacting with the terminal 19, and the operator then inserts the plug E of that subscriber into a socket D on one bar F (or this may best be done as soon as the operator has ascertained who is to be called) and the plug E of the calling-subscriber intoa socket on the same bar. Then, as will be seen, the connected subscribers may communicate with each other, the connection being afforded through the medium of one of the series of bars F.
  • the plugs E may terminate in hooks 70, as shown in Fig. 4, adapted to be suspended on the respective bars F, then suitably situated for the purpose, when, of course, the spring-jacks D may be omitted.
  • the operator may listen through the receiverR to the connected subscribers, as for the purpose of ascertaining whether or not they are still talkingor through, since thereby the 1ine-circuit U1 is closed with the branch circuit 10 of the connecting-bar F.
  • My improved system of teleph one-exchange material ly facilitates the work of the operator by enabling, among other advantages, the connections to be made at the switchboard without crossing the lines terminated by the plugs E, which tends to prevent confusion, the plugs E in the different rows thereof being so arranged with relation to the bars F or the spring-jacks thereon that a plug from any row may be applied to a connecting-bar at a point most directly in line with or nearest to it and without requiring any of the lines to be crossed by extending them to remoter points on the switchboard.
  • a switchboard having contact plugs, subscribers lines leading immediately to said plugs without passing intermediately through any form of resistance, said plugs forming the terminals of said subcribers lines and line-annunciators in the ground branches from the grounding-plates on which said plugs rest, substantially as described.
  • a switchboard having contact-plugs in rows and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs without passing intermediately through any form of resistance, branch circuits containing line-annunciators and normally closed by said plugs, connecting-bars for the temporary connection of subscribers 1ines,branch circuits containing the transmitter, receiver, generator and signal devices, said plugs being removable from their normal positions to open said annunciator-circuits and engageable with said connecting-bars,and switching means for connecting, at will, the generator, and transmitter and receiver circuits with the subscribers lines through said connecting-bars, substantially as and for the purpose set forth.
  • a switchboard having contact-plu gs in rows and forming terminals on the subscribers lines, branch circuits containing line-annunciators in rows, said branch circuits being normally closed by said plugs, a row of ring-ofi annunciators in branch circuits, connecting-bars, branch circuits containing the transmitter, receiver, generator and signal devices, said plugs being removable from their normal positions to open said line-annunciator circuits and engageable with said connecting bars, and switching means for connecting, at will, the generator, and transmitter and receiver and ring-off annunciator-circuits with the subscribers lines through said connecting-bars, substantially as and for the purpose set forth.
  • Atelephone-switchboard comprising the base A carrying contacts in rows, and the upright portion A carrying line-annunciators B in ground branches from said contacts, plugs carrying contacts and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs without passing intermediately through any form of resistance and said plugs being normally seated separably on said switchboard-contacts, and connecting-bars F with which said plugs engage in temporarily connecting subscribers lines, substantially as described.
  • a telephone-switchboard comprising the base A carrying contacts in rows, and the up right portion A carrying the rows of line-annunciators B in ground branches from said contacts, plugs carrying contacts and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs without passing intermediately through any form of resistance and said plugs being normally seated separably on said switchboard-contacts, connecting-bars F and socket devices D on said bars to receive the plugs, substantially as described.
  • a telephone-switchboard comprising the base A carrying contacts in rows, and the upright portion A carrying the rows of line-annunciators B in ground branches from said contacts, the roW of annunciators 0 having termin als 1;,plugs carrying contacts and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs Without passing intermediately through any form of resistance and said plugs being normally seated separably on said switchboard-contacts,connecting-bars F with which said plugs are engageable, and switch devices in circuit With said bars for connecting the circuits of the annunciators C With the linecircuits, through said bars, substantially as described.
  • a telephone-switchbcard comprising the base A carrying perforated contact-plates r in rows and affording seats, and the upright portion A carrying the rows of line-annunciators B in ground branches from said contact-plates, plugs E, each comprising a bar If surrounded by insulating material t and forming contacts at its opposite ends, said plugs being normally seated,separably, in upright position on said contact-plates and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs Without passing intermediately through any form of resistance and connecting-bars F with which said plugs are engageable, substantially as described.
  • a telephone-switchboard comprising the base A carrying perforated contact-plates r in rows and affording seats, and the upright portion A carrying the rows of line-annullciators B in ground branches from said contact-plates, plugs E, each comprising a bar f surrounded by insulating material i and terminating at its opposite ends respectively in contact-heads t and 23 said plugs forming terminals on the subscribers lines which lead immediately to the plugs without passing intermediately through any form of resistance and said plugs being normally seated at their heads 25 in upright position on said contactplates, connecting-bars F and spring-jacks D on said bars to receive the plugs, substair tially as described.
  • a switch device for circuits thereon comprising an insulated support carrying ter minals p and p of said circuits, a switch-lever Z passing through said support and fulcrumed on a metallic support on said insulated support and being adapted to contact at its end with the terminal 12 of a circuit, and controlling-springs m extending from said metallic support and bearing against opposite sides of the lever, substantially as described.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Structure Of Telephone Exchanges (AREA)

Description

(No Model.) 2 Sheets-Sheet 1.
- A. F. W. MEYER.
TELEPHONE EXCHANGE SYSTEM.
No. 565,627. Patented Aug. 11, 1896.
UNITED" STATES PATENT Fries;
ALBERT F. NV. MEYER, OF BLUE ISLAND, ILLINOIS.
TELEPHONE-EXCHANGE SYSTEM.
SPECIFICATION forming part of Letters Patent No. 565,627, dated August 11, 1896. Application filed August 8, 1895. Serial No. 558,581. (No model.)
' change shall be rendered peculiarly simple,
rapid, and effective.
Referring to the accompanying drawings, Figure 1 is a diagram showing the various circuits employed in my improved switchboard mechanism. Fig. 2 is a vertical sectional view of my improved switchboard,with several of the circuits, however, omitted by reason of their not being presentable, at least without undesirable confusion, owing to the nature of the view. Fig. 3 is an enlarged longitudinal sectional view of connected plugand-socket or spring-jack details; Fig. 4, a broken perspective View showing modified means for a purpose the same as the means illustrated in Fig. 3; Fig. 5, a broken sectional view showing a modified construction of a contact detail; Fig. 6, aview in sectional elevation of a preferred construction of switch; and Fig. 7 is a view, in the nature of a diagram, illustrating a modification.
A, Fig. 2, is the switchboard formed with a base A, from which rises the case A the front of which I prefer to divide into two panels A and A one for supporting the annunciators B and O, and the lower one for supporting the spring jacks or sockets D. In the ledge A of the base A, which maybe formed of wood, are provided any desired number of rows of vertical openings r 7', each of which is surrounded by a perforated metal contactplate 0*, the perforation in which alines with the adjacent opening 7' or 1-, and the plate is hollowed out, as shown in Fig. 2, on its upper side about its perforation to afiord a seat for the end of a plug E. The construction illustrated of the plug E comprises a metal rod 2, reduced toward one end, at the extremity of which it terminates in a rounded head if, the opposite end of the rod being expanded, as shown at and from this expanded portion'for some distance the rod is incased in insulating material 15 On the back ledge A of the 7 base A are provided binding-posts q for connection of the subscribers lines W WV,
ends 011 a common rock-shaft s, suitably j ournaled in the base A, the levers carrying near their free ends, at which each should extend at least approximately in vertical alinement with an opening 0 or r, as the case may be, pulleys s underneath which the connecting wires q pass in a manner to cause the weight of the levers to bear onthe wires, thereby holding them separate and taut and the plugs in their normal vertical positions, with the ends 79 thereof adequately tight against the plates r to afford good contact.
The spring-jacks D, which are supported in the lower panel A in parallel rows, may involve any suitable construction for adapting them to be connected with plugs, such, for example, as the plugs E. As shown in Fig. 3, each jack comprises a metal socket adapted to receive the reduced end of a plug, which is held'or steadied in place by a spring t extending forward from the rear end of the socket to engage the head 15 of the bar 25. Behind the jacks D are metal (copper) bars F, supported in horizontal position one above the other, each extending across arow of the IOO correspond in number and relative situation,
these annunciators being of any suitable variety and construction, the variety shown 'bein g the ordinary magnet and drop. Below the annunciators B is a row of ringing-off annunciators 0, similar to the others,though they should be wound to a higher resistance; and it is ordinarily necessary to provide but one of the annunciators O to, say, ten of the annunciators B, that being about the proportion of subscribers lines liable to be in use at any one time.
The circuits will be understood from the following explanation of the diagram: Each line-wire W of the system is connected by its insulated wire q, as shown in Fig. 1, with a plug E. From each contact-plate r there leads a wire to of the signaling-circuit through an annunciator B to ground. G is a switch device, the details of which are hereinafter described, for controlling the three terminals 19,19, and p From the terminal 1) leads the wire 10 through an annunciator O to ground. The'terminal p is at the end of the line Z02, which includes the generatorH and bell I of the operators call-circuit, and leads to ground. The terminal 19 is at the end of the line-circuit formed with the wire 10 which I cause to lead to ground througha fine or secondary induction-coil 0, between a primary induction-coil and a repeating inductioncoil 0 the coil 0 being in the circuit 10 containing the local battery K and the transmitter T, and the induction-coil 0 being in the circuit 10 containing the receiver R. A branch wire to leads from the contact-lever of each switch G to each bar or rod F. All these branchwires, however, connect with the one generator. I show leading from the wire a branch wire 10', terminating in an operators plug N, which carries at its end a rigid fork 07., adapted to engage with the rod of a plug E below its head if.
As will be observed, the circuits containing the annunciators B are normally closed by the plates r and expandedends t of the plugs E being in contact, so that when a sub- 7 scriber sends a ringing-up signal over his line WVthe annunciator B on that line lets fall its drop, indicating to the operator at the exchange that the subscriber desires connection with another line. Thereupon the operator raises the plug E, forming the terminal of the line over which the call was received, thus (by pulling the insulated wires q through the plate r and separating them from the contact end of the plug) breaking the signalcircuit to on that line, and applies the plug N to the plug E, whereby the operators talking-circuit w is connectedwith the subscriber, and enables the operator to talk with the latter through the transmitter T and listen through the receiver R. Upon ascertaining the connection desired by the subscriber the operator applies the plug E of the subscriber to be called to anyspring-jack I) of a disengaged connectingrbarF, and by throwing the lever of the switch G to contact with the terminalp the generator-circuit 10 is closed, thereby enabling the operator to ring up the desiredgnumber.
The construction of the switch G, I prefer to use is illustrated in Fig. 6. It comprises a plate on, of insulating material, from which depend the spring-terminals p and p and controlling-sprin gs m,which flank the switchlever Z, journaled on a plate Z, of insulating material, surmounting the plate m and coverin g the central opening therein,through which the switch-lever extends, and the controllingsprings m are held in place by the means for fastening the plate 1 to the plate m, a binding-post U being employed for connecting the wire to with one of the springs m and through the latter with the switch-lever with which the springpermanentlycontacts. Afterringing up the subscriber to, be called, the switchlever is released to resume its normal position of contacting with the terminal 19, and the operator then inserts the plug E of that subscriber into a socket D on one bar F (or this may best be done as soon as the operator has ascertained who is to be called) and the plug E of the calling-subscriber intoa socket on the same bar. Then, as will be seen, the connected subscribers may communicate with each other, the connection being afforded through the medium of one of the series of bars F.
If desired, the plugs E may terminate in hooks 70, as shown in Fig. 4, adapted to be suspended on the respective bars F, then suitably situated for the purpose, when, of course, the spring-jacks D may be omitted.
\Vith the switch-lever Z in its normal position of contacting with the terminal 19, either or both of the connected subscribers may-rin g off, since the wire 1.0, containing a ringing-off annunciator O, is then in circuit with the bar ;F, forming the connecting-link between them.
By turning theswitch-lever Z to contact with the terminal 19, the operator may listen through the receiverR to the connected subscribers, as for the purpose of ascertaining whether or not they are still talkingor through, since thereby the 1ine-circuit U1 is closed with the branch circuit 10 of the connecting-bar F.
As another formof contact means for the plugs E, I show that illustrated in Fig. 5, according to which the plug E passes through an enlarged opening r in the ledge A and bears at its end 25 against a contact-spring 'i, which will be understood to be connected with a line IV, the spring being fastened on a suitable insulating-support it below the ledge, and the weight of the lover s, controlling. the respective line g, causes the plug to force the spring i normally against an annunciator contact 9, connected by the line to with an annunciator B. The advantage of this construction is due to the double contact it affords, whereby poor contact, owing to corrosion of the contact-surfaces, is less liable to ensue.
As will be readily understood by those skilled in the art to which my invention relates, instead of groundingthe circuits, as
represented at O in Fig. l, metallic circuits may be employed throughout.
My improved system of teleph one-exchange materially facilitates the work of the operator by enabling, among other advantages, the connections to be made at the switchboard without crossing the lines terminated by the plugs E, which tends to prevent confusion, the plugs E in the different rows thereof being so arranged with relation to the bars F or the spring-jacks thereon that a plug from any row may be applied to a connecting-bar at a point most directly in line with or nearest to it and without requiring any of the lines to be crossed by extending them to remoter points on the switchboard.
To facilitate identification of the rows of jacks E, I distinguish them by difierent colors in a manner to cause each row of the jackheads to present a different color, and if the jacks are omitted the bars F are differently colored for the purpose.
The details shown and described as involved in my improved mechanism may be variously modified without thereby departing from my invention. Hence I do not wish to be understood as limiting my invention to such details, except where the intention so to do is manifest in the appended claims. One such modification, which suggests itself to me, is illustrated in Fig. 7, and consists in forming the levers s of conducting material (metal) connected from their free ends with the plugs E by wires g containing spiral-spring sections (1 the end of each lever behind its fulcrum being bent upward, as shown at 8 to extend underneath a contact-spring f, connected by a wire a: through a drop B to ground; and the lines W lead directly to the levers, by which they are connected with the plugs. With this construction, when the operator raises a plug B the lever connected with it is turned on its fulcrum to separate the end 8 from the spring f, thereby breaking the circuit of the line-annunciator the same as by raising the plug with the construction previously herein described.
What I claim as new, and desire to secure by Letters Patent, is-
1. In a telephone-exchange system, the combination with the switchboard, the contact-plugs thereof and the wires connecting the subscribers lines with said plugs, of conducting-levers bearing toward their free ends on said wires to hold them separate and taut and forming electrical connections between said lines and connecting-wires, substantially as described.
2. In a telephoneexchange system, the combination with the switchboard, the contact-plugs thereof and the wires connecting the subscribers lines with said plugs, of conducting-levers on a common fulcrum and bearing toward their free ends on said wires to hold them separate and taut and forming electrical connections between said lines and connecting-wires, substantially as described.
3. In a telephone-exchange system,a switchboard having contact plugs, subscribers lines leading immediately to said plugs without passing intermediately through any form of resistance, said plugs forming the terminals of said subcribers lines and line-annunciators in the ground branches from the grounding-plates on which said plugs rest, substantially as described.
4. In a telephone-exchange system,a switchboard having contact-plugs in rows and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs without passing intermediately through any form of resistance, branch circuits containing line-annunciators and normally closed by said plugs, connecting-bars for the temporary connection of subscribers 1ines,branch circuits containing the transmitter, receiver, generator and signal devices, said plugs being removable from their normal positions to open said annunciator-circuits and engageable with said connecting-bars,and switching means for connecting, at will, the generator, and transmitter and receiver circuits with the subscribers lines through said connecting-bars, substantially as and for the purpose set forth.
5. In a telephone-exchange system,a switchboard having contact-plu gs in rows and forming terminals on the subscribers lines, branch circuits containing line-annunciators in rows, said branch circuits being normally closed by said plugs, a row of ring-ofi annunciators in branch circuits, connecting-bars, branch circuits containing the transmitter, receiver, generator and signal devices, said plugs being removable from their normal positions to open said line-annunciator circuits and engageable with said connecting bars, and switching means for connecting, at will, the generator, and transmitter and receiver and ring-off annunciator-circuits with the subscribers lines through said connecting-bars, substantially as and for the purpose set forth.
6. Atelephone-switchboard comprising the base A carrying contacts in rows, and the upright portion A carrying line-annunciators B in ground branches from said contacts, plugs carrying contacts and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs without passing intermediately through any form of resistance and said plugs being normally seated separably on said switchboard-contacts, and connecting-bars F with which said plugs engage in temporarily connecting subscribers lines, substantially as described.
7. A telephone-switchboard comprising the base A carrying contacts in rows, and the up right portion A carrying the rows of line-annunciators B in ground branches from said contacts, plugs carrying contacts and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs without passing intermediately through any form of resistance and said plugs being normally seated separably on said switchboard-contacts, connecting-bars F and socket devices D on said bars to receive the plugs, substantially as described.
8. A telephone-switchboard comprising the base A carrying contacts in rows, and the upright portion A carrying the rows of line-annunciators B in ground branches from said contacts, the roW of annunciators 0 having termin als 1;,plugs carrying contacts and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs Without passing intermediately through any form of resistance and said plugs being normally seated separably on said switchboard-contacts,connecting-bars F with which said plugs are engageable, and switch devices in circuit With said bars for connecting the circuits of the annunciators C With the linecircuits, through said bars, substantially as described.
- 9. A telephone-switchbcard comprising the base A carrying perforated contact-plates r in rows and affording seats, and the upright portion A carrying the rows of line-annunciators B in ground branches from said contact-plates, plugs E, each comprising a bar If surrounded by insulating material t and forming contacts at its opposite ends, said plugs being normally seated,separably, in upright position on said contact-plates and forming terminals on the subscribers lines, said subscribers lines leading immediately to said plugs Without passing intermediately through any form of resistance and connecting-bars F with which said plugs are engageable, substantially as described.
10. A telephone-switchboard comprising the base A carrying perforated contact-plates r in rows and affording seats, and the upright portion A carrying the rows of line-annullciators B in ground branches from said contact-plates, plugs E, each comprising a bar f surrounded by insulating material i and terminating at its opposite ends respectively in contact-heads t and 23 said plugs forming terminals on the subscribers lines which lead immediately to the plugs without passing intermediately through any form of resistance and said plugs being normally seated at their heads 25 in upright position on said contactplates, connecting-bars F and spring-jacks D on said bars to receive the plugs, substair tially as described.
ll. In combination with a telephone-switchboard, a switch device for circuits thereon, comprising an insulated support carrying ter minals p and p of said circuits, a switch-lever Z passing through said support and fulcrumed on a metallic support on said insulated support and being adapted to contact at its end with the terminal 12 of a circuit, and controlling-springs m extending from said metallic support and bearing against opposite sides of the lever, substantially as described.
ALBERT F. WV. MEYER.
In presence of- J. H. LEE, J. N. HANSON.
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US20080209075A1 (en) * 2007-02-22 2008-08-28 Yahoo! Inc. Synchronous delivery of media content and real-time communication for online dating

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US20080209075A1 (en) * 2007-02-22 2008-08-28 Yahoo! Inc. Synchronous delivery of media content and real-time communication for online dating

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