US425594A

US425594A - Electric call

Info

Publication number: US425594A
Authority: US
Publication date: 1890-04-15
Anticipated expiration: 1907-04-15

Description

(No Model.) 2 Sheets-Sheet 1.

J. B. GU'RRIER.

BLEGTRIG CALL.

No. 425,594. Patented Apr. 15, 1890.

Wfmaasas \w EMMY I 9m h 6 e h s 8 u e e h S 2 L E n 0. 0 m T 0 F .E U m v d 0 M 0 m Patented Apr. 15, 1890.

u D .m Q ,M w% M37 z m 45 fm wi h 5 &Q. m m 0 NM w tern: cm, mom, vlmlna'mu, n. c.

UNITED STATES PATENT CEEICE.

JACOB B. CURRIER, OF LOWELL, MASSACHUSETTS, ASSIGNOR TO THE CUR- RIER TELEPHONE BELL COMPANY, OF MASSACHUSETTS.

ELECTRIC CALL.

. SPECIFICATION forming part of Letters Patent No. 425,594, dated April 15, 1890.

Application filed October 1'7, 1881. Serial No. 43,989- (No model.)

To all whom, it may concern: Fig. is an edge view of the caller in its case,

Be it known that I, JACOB B. CURRIER, of as shown in front View in Fig. 5. Lowell, in the county of Middlesex and State The general system of individual bells here of Massachusetts, have invented certain new referred to is shown and fully described in 5 and useful Improvements in Electric Calls my above-named Letters Patent, and its genand the Apparatus Connected therewith, of eral operation need not be here redescribed. which the following is a specification. On the circuit, 1, 2, and 3 represent three My improvements relate to the electric calldifierent stations provided with call bells, ing apparatus patented to me August 30, 1881, having each a different length of spring- 10 by Patent No. 246,374; and they consist in tongue to give it individual action with a placing the magnet and bell in a novel posiproper broken or undulatory current. The tion relatively to the bell-hammer and modicalling apparatus is placed at the central stafying the construction of the latter, as heretion l. inafter described, whereby I am enabled to O O are the ground-connections at each end I 5 make the calling-instrument operate more ofthe circuit. 5

surely and effectively in calling any particu- L is the battery. lar bell; secondly, in providing the calling- B is the bell. A is its magnet. instrument with an automatic circuit-break- H is the bell-hammer. The hammer is ing mechanism when stationary to save batplaced, according to my improvement here 20 tery-power and render the operation of the claimed, between the magnet A and bell B, bells more effective; thirdly, in providing instead of having the magnetand bell on the calling-instrument with a cam-shaped the same side of it. This arrangement is a drum or cylinder or equivalent crank-arm for great improvement on my former one for this enabling me to lengthen and shorten the vireason.

brating caller between any two bell-hammer In my former patent I have explained how lengths to the length of the one to be operated a spring-hammer enables itself to be kept over the line byasubstantially equal amount nearer to the vibrating time of the broken of rotation on its cam or crank axis to that reelectric current generated by the vibrating quired to adjust it between any other two spring g of the collar than is possible with a 0 bell-hammer lengths; fourthly, in attaching free swinging pendulum, thus causing the to the axis on which the cam or crank of the bell-hammer to continue to strike the bell calling-instrument moves a detent-lever and when once set in action instead of being providing the dial with a series of holes, into thrown out of striking time by rebounding which the detent fits, as hereinafter described, from the bell, as a free swinging pendulum is.

3 5 to cause the crank-arm or drum to be brought By experiment, however, I have discovered and held in exactly proper position, and thus that while the spring-hammer in sounding the readily give the vibrating caller the proper bell keeps the time of its own vibration near length to call the desired station on the cirenough to that of the vibrative current to cuit. thus continue to strike the bell, it does not 40 Inthedrawings,Figurelshows an electrical with my former construction exactly keep 0 circuit provided with a calling-instrument such time, and consequently some part of the and a series of individual bells, the caller electric force is wasted and the force of the having part of its face broken away to show blow of the hammer on the bell is thus diminits internal construction. Fig. 2 represents ished percep'tibly. Suppose, for instance, a

45 a modification of the calling-instrument with spring bell-hammer normally vibrating two the face of its case partly broken away to hundred and forty times per minute is used show its internal mechanism. Fig. 3 shows with my former arrangement. Taking the the face of the calling-instrument complete hammer in a state of rest, I am obliged to set ready for operation. Fig. i represents the the vibrating caller g so'that it will vibrate 50 individual bell of my improved construction. substantially two hundred and forty times per minute in order to set the hammer in motion by the vibrative current generated by the caller. Under the action of this current the bell-hammer will be set in vibration at its normal rate and constantly increase its swing until it strikes the bell. In repeated striking of the bell the vibrating hammer will have its rate increased somewhat above two hundred and forty times per minute, and its vibration thus varying from that of the current generated by the caller, which remains constant, part of the electric force is expended in acting against the spring while it is farthest away from the magnet and least susceptible to its influence, and is accordingly wasted.

My present arrangement overcomes this diificulty in the following manner, and produces a louder alarm with the same volume ofelectric force. The magnet being on the opposite side of the hammer from the bell, the rebound of the hammer from the first blow on the latter sends it with accelerated motion nearer to the magnet and directly into its strongest attractive force, giving it sufficient power to control the motion of the hammer. The magnet therefore holds onto the hammer and detains it at the farthest point of its rebound from the bell until the current is broken and the hammer released to spring forward againstthe bell. This operation is constantly repeated and the hammer kept vibrating in time with the make and break of the current instead of out of that time, thus making the motion of the bell-hammerand vibrating caller g coincide while the bell is being sounded. In order to aid this action of the magnet, I make the armature of the hammer and its striking partsubstantially in one piece and make the flexible part of it entirely between the hammer-armature and its point of support. This construction gives the magnet V greater leverage over the striking-hammer, and at the same time a larger mass of soft metal to act upon, thereby increasing its effi- 3 ciency. It also diminishes the amount of weight to be carried by the spring and en ables me to use several more bells on a circuit at'higher rates of vibration than was before I practicable.

My second improvement consists in so placing the lever in and its springnthat the battery-circuit will be connected with the line only when the vibrating caller is in operation, and will be connected then only through the contact-point k of the vibrating caller. The caller will thus automatically break the circuit at the instant that the lever is released. This prevents induced currents of electricity from? flowing over the circuit and the bell-hammer: armature from clinging to its electro-magnet. g

The importance of this is considerable.

In the caller shown in Fig. 1, q is the line connected with the battery which is connected i to the caller-actuating lever-studp. The metal arm 0 of the wooden lever m, which actuates the vibrating caller, comes into contact with' the metal stud r when the lever m is moved out of the way of the vibrating caller, "and the the battery-circuit. Suppose we have an electrical circuit with a bell at'station 1 vibrat-.

ing five hundred times per minute and one 2 at station 2 vibrating five hundred and fifty If after using station 1 bell its hamy times. mer is immediately released from magnetic influence by the breakiugbfthe ClTOlllt, I can therefore immediately can No. 2 bell; but if the circuit be not thus broken there is a hability of sounding No. 1 bell in calling No. 2,

because the hammer-armature may cling to its electro-magnet until released bythe break first made in calling the next bell. The automat c breaking of the circuit in the caller, as described, sensibly overcomes this difficultyand enables me to place more'bells ona circuit.

Instead of the cylindrical wheel or drum 1) shown in the patent before referred to for lengthening and shortening my vibrating caller g, I have adoptedacylinder rotati ngon the axial s'tud,which is provided with a cran karm s, to which the upper end of the spring of the caller ishttached, which with each for-.

ward movement of the index-hand attached to the cylinder will shorten the spring vibrating part of the caller less than did the last preceding movement of the index-hand through an equal space over thedial-face. Another form to accomplish thisis shown in Fig. 2, in which is a cam-shaped cylinder which constantly diminishes the amount which it shortens the vibrating caller, as it continues to shorten it in proportion to 'a given amount of rotation. The reason of this construction is that it requires a greater shortening of the vibrating caller to adapt it to two bells adjacent in rate of vibration in the lower speeds than it does in the higher. For instance, suppose the lowest bell-ham-mer in vibration to be two hundred and forty times per minute and the next greater to be two hundred and ninety times per minute. It will require a much greater shortening'of the length of the caller betweentheir lengths ITO than it would between thelengths'of twobellhammers when the lowest vibrated one thousand times per minute and the next highest vibrated one thousand and fifty times; hence I proportion the cam shortenin'g cylinder or crank-arm so that with an equal amount of rotation on its axis it will so shorten the vibrating caller as to adapt it to'two consecutive bells whether vibrating at the higher or lower speeds. This enables meto move the dial-hand which is attached to the axis of this cam or arm over an equal space to call any bell after calling the next one below it in vibration.

' My fourth improvement consists in attaching to the index-hand b of the cylinder 1) an extension or prolongation b on the opposite side, of its axis from the hand and providing this prolongation with a pin or detent projecting inward and made to accurately fit a series of holes in the dial-face 1' 2 3 &c. These holes are so placed that this prolongation of the pointer, being elastic, springs the detent into the hole at the exact point required to adapt the length of the vibrating caller g to some one of the bell-hammers on the line. This not only saves time and care on the part of the operator in calling any hell, but it is valuable in setting the index to call a bell having its hammer vibrating on a high number-as, for instance, eleven hundred vibrations per minute-because the higher the number of vibrations per minute the greater the accuracy required in lengthening or shortening the vibrating caller g to the exact extent necessary to operate the bell-hammer vibrating at that rate. By means of the holes 1 2 3, &c., and their detent I am enabled to attain the greatest exactitude and celerity in this respect, where it is so important. The detent also locks the cylinder in this exact position and prevents it from being moved by accident.

What I claim as new and of my invention 1. The combination of an electric circuit, a vibrating circuit-breakin g mechanism therein arranged to make and break the circuit regularly and automatically at a predetermined rate of vibration, and an alarm mechanism in said circuit, consisting of magnet A, bell B, and the vibrating striker H, located between them, provided with an armature and arranged to automatically vibrate synchronously with said circuit-breaker, whereby the variation in the rate of vibration of the striker produced by its blow upon the bell will be overcome by the magnet upon the rebound of the striker toward it, substantially as described.

2. The combination of an electric circuit, a vibrating circuit-breakin g mechanism therein arranged to make and break the circuit regularly and automatically at a predetermined rate of vibration, and an alarm mechanism in said circuit, consisting of magnet A, bell B, and the vibrating striker I-l, having its striking part and armature formed of one rigid piece of metal and its elastic part en-.

tirely between the latter and its point of support, said striker being arranged to automatically vibrate synchronously with said circuitbreaker, whereby the production of secondary and interfering vibrations between the armature and striking part of the striker by its blow upon the bell and the consequent disturbance of its synchronous vibration are avoided, substantially as described.

3. The combination of an electric circuit, the vibrating circuit-breaker g, having its spring portion adjusted to make and break the circuit automatically at a predetermined rate of vibration and to be held in position to break the circuit when its vibration ceases, and two alarm mechanisms in said circuit, one of which has the spring portion of its striker adjusted to automatically vibrate synchronouslywith said rate of vibration of the circuit-breaker and the other of which has the spring portion of its striker adjusted to vibrate at a substantially different rate of vibration not affected by the circuit-breaker, substantially as described.

4. In combination with the circuit of individual call-bells, the caller g and its arm I), provided with the arm I) and its detent, and the corresponding holes 1 2, &c., placed to adjust the caller to the length to call one or more of said bells, substantially as described.

JACOB B. CURRIER.