US1075421A - Electric signaling system. - Google Patents

Description

R. M. HOPKINS.

ELEGTRIG SIGNALING SYSTEM.

APPLIUATION FILED JAN. 27, 1913. L75A21 Patented Oct. 14, 1913.

2 SHEET$SHEET 1.

INVENTOR R. M. HOPKINS.

ELECTRIC SIGNALING SYSTEM.

APPLICATION FILED JAN. 27, 1913.

1,075,421,, Patented 0011.14, 1913.

2 SHEETS-SHEET 2.

W/T/VESSES NV NTOR M/Q WVWMKM/M UNITED srarns rarnnr cur ies.

RICHARD M. HOPKINS, OF NEW YORK, N. Y ASSIGNOR TO THE AMERICAN DISTRICT TELEGRAPH COMPANY, A. CORPORATION OF NEW JERSEY.

ELECTRIC SIGNALING SYSTEM.

Specification of Letters Patent.

Patented Oct. 1 a. 1913.

Application filed January 27, 1918. Serial No. 744,325.

'0. all whom it may concern:

is a specification, reference being had to lathe accompanying drawings, which form a part hereof.

This invention relates to electric signaling systems.

It is adapted for various uses but was especially designed and is partic r larly adapted for use as a fire alarm system.

In systems of this character,

it h as been the practice heretofore to arrange one-or more alarm instruments, such as gongs, and one or more switch instruments or signal transmitters in series with a common source oiv current supply cu it.

The current required t and in a normally closed ciro operate such a system is considerable and inasmuch as the circuit is normally closed and for periods or there IS a great waste or operates at long intervals short durat on, current energy during the ordinarily time that the alarm or signal instruments are not in actual operation.

The present invention seek provide a s primarily, to

reliable and efiicient system which shall effect agreat saving in cur 'cntconsuniption.

This is accomplished by main-' taining in the normally closed signal circuit a currentof minimum then increasing the current strength and sufiiciently to operate the signal instrument or instrumerits in the circu t at such time as it is desired that the signal instrument or instruments shall be in active oper ..'\ssociated with the test signal designed to oper derangement of the signal ation.

s gnal circuit is 21 arts when any system occurs,

such as a break at any part or the circuit or failure of current therein, and thereby serving as a test of the etliciency o dition of the system.

In the accompanying part of this specification, and in which reference numerals designate parts, Figure 1 is a diagram in its preferred form.

r working condrawings forming l ilre corresponding of the system Fig. 2 is an end elevation of one or the relays employed in the system. Fig. 3 is a diagram 0 in modified arrangement.

t the invention stops E24 and 25, and is normally Referring now to the invention as shown in Fig. 1, 1 is an electric signal instrument which may be of any suitable design, but is here shown as a gong.

2 is a switch instrument or signal transmitter and may be of any suitable design. It operates the circuit controller 3 and is here shown in a form well known in the art.

l is a low resistance magnet. I

5 is a high resistance magnet and 6 is a 6 resistance device. 7

The signal instrument 1, circuit controller 3, magnets 1 and 5, and resistance 6 are all arranged in series with battery 7. and in a normally closed signal circuit. This circuit maybe traced as follows :-from battery 7 through wire 8, binding post 9, wire 10, magnet 4, wire 11, binding post 12, wire 13, magnet 1% oi the signal instrument 1, wire 15, circuit controller 3, wire 16, binding post 17, wire 18, magnet 5, wire 19, resistance (3, wire 20, binding post21, and wire 22 back to battery'7. Magnet 5 is wound to a high resistance, say about 2,000 ohms, and magnet 4 is wound to a low resistance, say about 12 ohms. The resistance 6 is increased in accordance with the increase in the number of signal instruments that may be included in the signal circuit. In the drawing, the resistance 6 includes two resistance tubes, only one signal. instrument being shown in the signal circuit. The 'n'al circuit, as described, normally carries a relatively small'current because of the high resistance due to magnet 5 and resistance (3. That portion of the circuit extending from binding post 17 through wire 18, magnet 5, wire 19, resistance 6 and wire 20 to clip 38 maybe termed a high resistance circuitportion because in this portion of the signal circuit is included the resistance which is responsible for the small current normally carried by the signal circuit. It will be understood, of course, that most of the resistance required in this circuit-portion may be included in magnet 5 alone or in resistance tubes alone, or the resistance may be distributed between these two devices, or otherwise provided in this circuit-portion.

The signal instrument 1 is of such charac- 'terthat it is responsive to' arclatively-large current only. In this signal instrument, as shown in the drawings, the magnet lt'operatcs armature 23 which vibrates between v I retracted by spring 26 against stop 25. ()n the upper end of the armature is mounted a spring 2? which carries a bell tappcr 28 arranged to strike the gong 29 by bending spring 27 after the armature has been arrested by that one of its stops nearest the gong.

The signal transmitter 2, as shown, is of the usual type. It includes the circuit controller 3 which has a finger 30 on one of its springs designed to be operated to make and break the signal circuit by the teeth on the signal wheel 31. -The signal wheel 31 is operated by the usual spring actuated gearing 32 which need not be described. WVhen the lever33, connected with this gearing. is depressed, the springis wound up. When the lever is released the gearing rotates the signal wheel'31 counter-clockwisc,

the teeth on the-wheel 31 acting upon finger 30 to make and break the signal circuit such number of timesand at such spaced intervals as is determine'dby the number and position of the teeth on the signal wheel. The signal instrument is arranged to respond in accordance with this operation of circuit controller 3 by the signaluwheel. In the present instance, the signal wheel 31 has its teeth so arranged as to transmit to the signal instrument through the circuit controller 3,

the number 123 which number is the desig- ,nation of the particular station to which the signal transmitter pertains. There may.

be as many signal transmitters and as many signal instruments connected in the circuit as the requirements of the service demand. These'would ordinarily be placed at different localities, such' as different parts of a building or buildings. It will be seen that, although the circuit is shown as closed, magnet '14 is unresponsive to the current, the armature .23 resting against the stop 25, This is due to the fact. that the current in the circuit is greatly reduced, below that required to make magnet 14 respond, by the hi gh resistance circuit-portion which is normally included in the signal circuit. When the current in the circuit is raised to the requisite value, magnet 14 responds and pulls over its armature against stop 24. When, thereafter, the current in the circuit is reduced to normal, the armature flies back against stop 23, spring 27 bending to per mit the tapper 28 tostrike the gong 29 one beat. The manner in which the gong operates to sound the required signal number in response to the electric impulses produced by the signal transmitter will be explained hereinafter.

Extending around the high resistance circuit-portion, heretofore described, is an auxiliary circuit member extending from the binding post 17, through wire 34, contact armature 36 of magnet 55, wire 37 which is connected to and moves with the armature, clip 38, to wire 20. This auxiliary circuit member is normally open at contact 35, the break being controlled by armature 30. \Vhen armature 36 drops to close this circuit member, the high resistance circuit-portion is shunted 'out of the signal circuit,.the auxiliary circuit member then included in the signal circuit being of much lower resistance. This increases the current in the signal circuit to the requisite value to make the gong magnet '14 respond when the circuit is next closed at circuit controller 3. Armature 36 and contact 35 may be termed a current changer inasmuch as they operate, when closed, to increase the current and, when separated, to diminish the current which may How in the signal circuit. The aufiiliary circuit member thus traced through armature 36, from contact post 1-7 to wire 20 may be termed a current-increasing circuit member, inasmuch as this circuit cuit, operates to increase the current in the signal circuit. Magnet 5 exercises its control over the current-increasing circuit member when it releases armature 36.

In the normal condition of the circuit, magnet 5 acts to hold up its armature so as to maintain the break in the current-increasing member at contact 35. After armature 36 has been released, it is moved back or restored to normal position by the operation of magnet 4. This magnet.- which may he termed the restoring magnet, may be made to operate in any. suitable manner to restore armature 36 to normal position. As shown in the drawings, its action upon this armature is mechanical. It is provided with projecting pole pieces-39 which pass through holes in the,armature40. The armature is provided with a finger 41 adapted to move against armature 36 and restore it to normal. position when its own armature 40 is attracted by magnet- 4. Armature 40 is held normally retracted by spring 42 attached to the adjusting screw 43.

44 is an adjustable stop to regulate the throw of armature 40 and its finger 41. Restoring magnet 4 is relatively slow acting, being so designed to permit the armature 23 of signal instrument 1 tobe attracted before magnet 4 lifts armature 36.

.to battery. "When armature 36 is held up by magnet 55, the circuit of this test signal is broken at contact 47. If any derangement of the system occurs. such as a break at any part of the signal circuit o'r av failure of current frombattery 7, magnet 5, be-

, whenever the latter is released.

comes deenergized and drops its armature 36, thereby closing at contact 37 the clrcult of the test signal 45 which thereupon gives notice of the inefficiency or inoperativeness of the system Inasmuch as armature 36 of magnet 5 vibrates between back contacts 35 and 47, on one side of the armature, and front stops 49 and 50 on the other side of the armature, special provision is made to insure the closing of'contacts 35 and t? by the armature vision is indicated inFig. 2. In this figure, the coils of magnet 5 are shown as supported by the base 51 on which are mounted-bearings 52 and 53 to receive the rock'shaft 54. Armature 36 is provided with a trunnion 5 5 turning in a bearing in the middle of the shaft 54, said trunnion and rock shaft ex tending at a right angle to each other. As thus constructed, the armature is capable of tilting on both of. its pivotal supportsand is sure to make a reliable electrical connection with botlycontacts 35 and 47, Whether or not such contacts are accurately adjusted to the same distance, from the poles of th magnet or the stops 49 and 50. -Armatinre 36 may be retracted against its back contacts 35 and t7 either by a'spring or gravity. This special mounting of the armature is not herein claimed; it being the invention of another party and for which an application for a patent will be made.

The operation on the system is as follows:

. rent is maintained in the signal circuit only When lever 330i the signal transmitter is depressed and then released, signal wheel 31 rotates counter-clockwise. The first tooth lifts finger 30 and opens circuit controller This breaks the signalcircuit and de energizes magnet 5 whichthereupon releases its armature 36 to-close' contact 35, and thereby cut into the si al circuit said ourrent-increasing circuit member and sh nt or cut out the high resistance'circuit-portion. The first toothof'signa-l wheel '31 now passes finger 30, thereby permitting cir cuit controller 3 to close-and complete the" signal circuit. The high resistance circuitportion including high resistance magnet 52 and resistance 6 being now shunted from the signal circuit, the current inthe signal circuit'is greatly increased. Magnet 14 thereupon responds tothe increase inv current and attracts its armature 23. Restoring magnet also responds to this increase in current and-attracts its armature but lags, in its action on its armature, somewhat behind the quicker action of magnet 14 on its'armature. In the present instance. thisis provided for by the longertravel required of armature' tObefore it can lift armature 36,

and the adjustment of its springtQ. As

' armature .40 completes its movement toward magnet 4-, finger 41 lifts armature 36 from Such procontact 35, thereby cutting out the current increasing circuit member and again cutting in the high resistance circuit-portion. lv'iagnet 4, thereupon, releases its armature if) and magnet 14 also releases its armature 23;

be sounded-on theg ong 29, constituting the signal number 2. W hen the following three teeth; which are also relatively close together but spaced farther from the preceding two teeth, act on finger 30 they cause three quick strokes to be sounded on the gong, thereby transmitting the signal number 3, andthus completing the signal 123.

It will be seen that in the system described the si nal circuit is normall closed 3 '3 with a current of minimum strength maintained in it during thelong intervals of inactivity of the circuit and that. during such time as the system is actively in operation, the current strength is raised to and-maintained at its maximum value during very short intervals of time, In fact, during the operation the signal transmitter in the preferred arrangement as shown in the drawlngs, the maximum strength of the car:

during" the moment after each tooth on thesignal wheel 31 has passed finger 30 and before the consequent movement ofarmature 36 has been effected.-

magnet 4,"l1oldi11g.1nagnet 5 and signal instrument 1' need not all be. necessarily. normally included in series in the signal circuit, as is the casein Fig. 1. These devices.

or some of them may be included in separate circuits. These modifications are illustrated in Fig. In the arrangement there shown, when the current increasing circuit member is included in the signal circuit. it adds an additional battery to increase the current in the signal circuit to its maxi-mum. More over, the cuwent-increasing circuit member isv part of a normally closed circuit separate from the signal circuit and includes v the latter,- on this return movement, causing one stroke to be given on gong 29, z. e.

The invent-ion is susceptible of various tery is divided into two portions 7 and 7 The normally closed signal circuit may be traced from battery 7, through wire 56, bind ng post 5'5, wire'58, magnet 5, wire 59, contact 50, armature36, clip 61, wire 62, binding post 63, wire 64, circuit controller 3, wire 65, magnet 14 of sigr l instrument 1, and wire 66 back to battery 7 It will. be noted that resistance 6 is omitted from this circuit, the resistance of magnet 5 being sufficient for the purpose in View of the reduced output of current from battery '1' armature 36, as in Fig. 1. The current-increasing circuit member, including restoring magnet 4t, may be traced from battery 7', through wire 67, magnet l, wire 68, to clip 72 which connected to contact 47. The rest of the closed circuit, of which this'current-increasing circuit member is normally a part, may. be traced onward from clip 72 through wire 66, coil 81 of instrument 69, resistance 70, wire 71, binding post 57 and wire 56 hack to battery 7. Instrument 69, which may he a voltmeter, contains a circuit controller 73 which is held normally open by coil. 81 and, when closed, acts to close the circuit of the test signal as follcwss i rom battery 74, through wire 75, hindii i post 63, wire 62, Wire 76, circuit controller 73, wire 76, and test signal &5 back to battery 74?. ll. the circuit of magnet and coil 81 is ruptured at any point or battery 7 fails, coil 81 is dcenergized, circuit controller 73 (noses and test signal 15 gives the alarm. Contact 35 is connected by wire 79 with wire 78 so that it a rupture occurs at any point in the signal circuit or battery Wiails, thereby deenergizing magnet 5 and dropping armature 36, a similar alarm will be indicated by the test signal ln this case coil 81 is deenergized by the shunt established when. armature .36 drops and connects wire 68, with wire 62 through clip 72, contact 4-1, armature 36 and clip 61 to wire 6", so that current from battery '4', which had pre 'iously been flowing through coil 81, now flows from the battery through wire 6?, magnet l, wire 6%, clip '72, contact 47, armature 36, clip 61, wires 62 and or, circuit controller 3, wire 65, magnet wire 66 and battery 7 to battery 7" stance 7%,which is in the branch with .l 61 serves the purpose of cuttingdowu the currentlhrough magnet t and coil 81 lo the required amperage and maybe ad A. i /Ingest is energized and holds up its net 4%..

justed to'suit the requiren'lents. Nhen coil 81 is shunted, as just described, circuit con troller closes to complete the circuit through test signal 45 as follows:-from battery 74, through wires and 62, clip 61, armature 36, contact .35, wire-79, Wire 78, and test signal 45 back to battery. Thus,

the testsignal as acts as a test both for the normally closed signal circuit, and for the l separate normallyclosed circuit which includes the currentnncreasmg circuit memer through magnet 41,

In the operation of the system shown in I Fig. 3, when signal transmitter is operated, the break at circuit controller 3 de 6' energizes magnet 5 which, thereupon, .r'eleases its ,a-rmature. This cuts out the high resistance circuit-portion which includes binding post 57, wire 5.8, magnet 5 and wire 59 to contact 50, by the break at contact 50 rentincreasin-g" circuit member, which includes magnet 4, by closing the contact .between armature 36 and contact 47, and this operation of the armature 36 at contacts 47 and 50 connects both batteries 7" and Win series with signal instrument 1 and magf- The circuit now may be traced as follows:-from battery 7 through wire 67, magnet 42, vire 68, clip 72', contact 47, armature 36, clip 61, wire 62, wire 64, circuit controller 3, wire 65, signal instrument 1, wire 66, battery T and Wire to battery 7. /Vhem'noW, circuit controller 3 closes, magnet 14 attracts its armature 23 to strike the gong 29 and magnet 4 thereafter operates to .lift armature 36 to its normal position, whereupon magnet 14: releases its armature 23. It will he noted that in this case the gong 29 has'been shifted so that it is struck on the front stroke of the armature, or when the circuit is closed at circuit controller 3 with the current at maxiand connects into the signal circuit the curmum, whereas, in Fig. l, the gong is struck on the back stroke of the armature or when the circuit is broken at circuit controller 3.

It will be understood, of course, that in j the signal instrument the armature 23,

which in the drawings is shown as noting mechanically on the gong, may be arranged to act elect 'ically to operate a local gong circuit, and that various changes in.addition to those pointed out intne foregoing may scope of the invention.

What-l: claim is:

1. The combination with a normally closed signaling circuit, of a source of electrical in said circuit and thereby operate the signal instrinuent; normally energized electromagk he made without departing from the energy adapted in the normal'condition' ofi netic means arranged when deenergized to operate the current changer; automatic means for restoring the current changer to normal condition after the sending of a signal, and a switch instrument controlling said electromagnetic means.

2. The combination with a normally closed signaling circuit, of a source of electrical energy adapted in the normal condition of the circuit to supply a relatively small current thereto, a signal instrument in the circuit responsive only to a relatively large current, means including an electromagnetically actuated switching device for increasing the current in the circuit, and electromagnetic means for automatically restoring the current changer to normal condition after the sending of a signal.

3. The combination with a normally closed signaling circuit, of a source of electrical energy adapted in the normal condition of the circuit to supply a relatively small current; a signal instrument in the circuit responsive only to a relatively large current; a current changer operating to vary the current in said circuit and thereby operate the signal instrument; electromagnetic means for operating the current changer comprising a high resistance magnet in the normally closed signal circuit vfor holding the currentchanger in normal position and a low resist-r ance restoring nagnet for returning the cur rent changer to normal position; and a switch instrument controlling said electromagnetic means.

4:. The combination with a normally closed signaling circuit, of a source of electrical energy adapted in the normal condition of the circuit to supply a relatively small current; a signal instrument in the circuit responsive only to a relatively large current; a current changer operating to vary the current in said circuit and thereby operate the signal instrument; electromagnetic means for operating the current changer comprising a high resistance magnet for holding the current changer in normal position and a low resistance restoring magnet having'a 'low acting armature arranged to mechanically move the current changer into normal position; and a switch instrument controlling said electromagnetic means.

5. The combination with a normally closed signaling circuit, of a source of electrical energy adapted in -the normal condition of i'he circuit to supply a relatively small current; a signal instrument in the circuit responsive only to a relatively large current; a current changer operating to vary the cu rent in said circuit and thereby operate the signal instrument; electromagnetic means normally on closed circuit. for operating the current changer comprising a magnet in the normally closed signal circuit. for holding the (lll'l'tlll changer in normal position and a restoring magnet for returning the current changer to normal position; and an automatically operating make-and-break signal transmitter in the signal circuit and controlling said elect-romagnetic means.

6. The combination with a normally closed signaling circuit, of a source of electrical energy adapted in the normal condition of the circuit to supply a relatively small current; a signal instrument in the circuit responsive only to a relatively large current; acurrent changer operating to vary the current in said circuit and thereby operate the signal instrument; electromagnetic means normally on closed circuit for operating the current changer comprising a high resistance magnet for holding the current changer in normal position and a low resistance restoring magnet having a slow acting armature arranged to mechanically move the current changer into normal posit-ion; and a switch instrument controlling said electromagnetic means.

7 The combination with a signaling circuit normally including a high resistance circuit-portion; a signal instrument and a signal transmitter connected with the circuit beyond said high resistance circuit-portion; a current-increa sing circuit member; a circuit controller operating to cut out of the signal circuit said high resistance circuitportion and cut into said signal circuit said current-increasing circuit member. and vice versa; a holding magnet in said high resistance circuit-portion normally energized to hold said circuit controller in normal position to cutout of the signal circuit the current-increasing circuitmember and cut into said signal circuit the high resistance circuit-portion; a magnet responsive when the current-increasing circuit member is cut into the signal circuit and acting to move the circuit controller back to normal position.

8. The combination with a signaling cir= cuit normally including a high resistance circuit-portion; a signal instrument and a signal transmitter connected with the circuit beyond said high resistance circuit-portion; a current-inrreasing circuit member; a circuit controller operating to cut out of the signal circuit said high resistance circuitportion and cut into said signal circuit said current-increasing circuit member and Vice versa; a magnet controlling the} movement of the circuit controller in one direction; and a magnet controlling the movement of the circuit controller in the other direction.

9. The combination with a signaling" circuit normally including a high resistance circuit-portion; a signal instrument and a signal. transmitter connected with the circuit beyond said high resistance circuit-portion: a current-increasing circuit member; a cir- (-nit (Ulltl'llllvl' operating to cut out oi"- the portion and cut into said signal circuit-said current-increasing circuit member and vice versa; a magnet controlling the movement of the circuit controller in one direction; and a magnet controlling the movement of the circuit controller in the other direction, said latter magnet being responsive when I the current-increasing circuit member is cut into the signal circuit.

10. The combination with a normally closed signaling circuit; a normally inactive signal instrument in said circuit; a current changer operating to vary the current in said circuit and thereby operate the signal instrument; a normally energized holding magnet for said current changer; and a normally unresponsive restoring magnet-operating to restore the current changer to normal position after it has been released by the closed signalingcircuit, of a source of else-- trical energyadaptcd in the lhbrmal condi-.

tion of the circuit to supply a relatively small current; a signal instrument in the circuit responsive only to a relatively-large current; a current changer operatin to vary the current in said circuit and there y operate the signal instrument; electromagnetic means for operating the current changer comprising a holding magnet for holding the current changer in normal position and a restoring magnet for returning the current changer to normal position; a switch instrument controlling said electromagnetic means; and a test signal controlled by said holding magnet.

13. The combination with a normally closed signaling circuit',.of a source of electrical energy adapted in the normal condition of the circuit to supply a relatively small current thereto; a signal instrument in the circuit responsive only to. a relatively large current, means including an electroma netically actuated switching device for increasing the current in thec1rcuit,.auto

matic, means for restoring the current.

changer to normal condition after the sending of a signal, and atest signal controlled by said switching devloe. I V p 14. The combination with a signaling circuit "normally including a" high resistance circuit-portion; a signal instrument and a signal transmitter connected with-the c1rcuit beyond said high resistance circuit-portion; a current-increasing circuit member; a circuit-controller operating to cut out of the signal circuit said high resistance circuit-portion and cut into said signal circuit said current-increasing circuit member and vice versa;-a holding magnet normally energized to hold said circuit controller innormal positionto cut out of the signal circuit the current-increasing circuit member and cut into said signal circuit the high resistance circuit-portion; a magnet responsive when the current-increasing circuit member is cut into the signal circuit and acting to move the circuit controller back tonormalposition; and a test signal arranged to operate when the normal current in the signal circuit isinterrupted.

15. The combination with a normally closed signaling circuit, of a source of electrical energy adapted in the normal condition of the circuit to supply a relatively small current; an audible signal instrument in the circuit responsive only to a relatively large current; a current changer operating to vary the current in said circuit and thereby operate the signal instrument; automatic means for restorin the current changer to normal condition a ter the sending of a signal; and a signal transmitter controlling said current changer and adapted to send at each operation a group of signal impulses of relatively lar 'e current over the signal circuit to cause t e signal instrument to respond to each impulse of the group.

16. The combination with a normally closed signaling circuit, of a source of electrical energy adapted in the'normal condition of the circuit to supply. a relatively small current; a signal instrument in the circuit responsive only to a relatively large current; a current changer operating to vary .the current in said circuit and thereby operate the signal instrument; electromag netic means for operating -the current changer comprising a magnet for holding the current changer in normal position and a restoring magnet for returning the current changer to normal position; and a signal-transmitteradapted to send a group of current impulses into the signal circuit and thereby cause the signal instrument to re spond in accordance with said impulses. j.

' 17 The combination with a signaling circuit including an audible si nalinstrument,

saidcircuit normally including a high resistance circuit-portion; a current-increasing circuit member; a circuit controller operating to cut out of the signal circuit said high resistance circuit-portion. and cut into said .signal circuit'said current increasing circuit member and vice verse/g a holding magnet in are high resistance circuit-pwionnonnally energized to hold said circuit controller in normal positimr'to cut out of the-signhl:cir-' cuit the currentincreasing circuit ineinlici' instrument in respond in accordance with 10 and cut into said signal circuit the high i'csaid impulses.

sistancecircuit-portion; a magnet responsive This specification signed and Witnesqed when the (:lllil'Qllt-lHCIQfiSlHg circulit member this 24th day of January, A. D. 1913,

is cut into tie si 'nzil circuit am actin to J 7 move the circuit. Eontmller back to 1105113]. RICHAID H01 knlb' position; and a signal transmitter adapted Witnesses:

to send a group of current impulses into the IDA G. GILMORE,

signal circuit and thereby cause the signal WVORTIIINGTON C. CAMPBELL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C.

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