US2360666A - Electric signaling apparatus - Google Patents

Description

Oct. 17, 1944. G. R, FISH F'LECTRIC SIGNALING APPARATUS Filed Dec. 23, 1942 I Z Y 77/44 2 3 mi INVENTOR 6 50 66: IZSH- 34a BY MW ATTORNEY Patented Oct. 17, 1944 UNITED STATES PATENT OFFICE ELECTRIC SIGNALING APPARATUS George R. Fish, Norwalk, Conn., assignor to Edwards and Company, Inc., Norwalk, Conn, a corporation of New York 7 Application December 23, 1942, Serial No. 469,922

8 Claims.

This invention relates to electrical signaling apparatus, more particularly to an audible signaling device such as a gong or bell.

One of the objects of this invention is to provide a simple, practical and dependabl electrical signaling device of the above-mentioned charactor in which striking of the sounding element, such as a gong, may be repeatedly effected at the desired low rate, and thus also to improve the sound produced by the Vibrating sounding element. Another object is to provide a slow-acting electrical audible signaling apparatus that Will be capable of dependable operation and control at voltages that are also on the order of 110 volts and capable also of functioning on either alternating current or direct current circuits.

Another object is to provide an electromagnetic striker mechanism for a sounding element such as a gong in which clean and neat impacting of the sounding element may be achieved by the striker, in the desired low rate of succession of impacts, and in a simple and reliable manner maintain the en rgy of individual impacts free from detrimental effects even though the motion causing the impact is utilized for making and breaking the circuit. Another object is to provide an apparatus of the above-mentioned character in which, though the striker may be repeating its cycles of movement at a low rate, dependable making and breaking of the circuit of the electromagnetic winding employed may be achieved in a dependable and inexpensive and eflicient way.

Another object is to provide an apparatus of the above-mentioned character which will lend itself to efiicient and inexpensive manufacture. Another object is to provide in such apparatus of the above-mentioned character structural features that will facilitate assembly and even facilitate the creation of sub-assemblies and thus make for more efiicient manufacture.

Other objects will be in part obvious or in part pointed out hereinafter. v

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts as will be exemplified in the structure to be hereinafter described and the scope of the application of which will be indicated in the following claims.

In the accompanying drawing, in which is shown by Way of illustration one of the various possible embodiments of the invention,

Figure 1 is a rear elevation of the apparatus as seen with the rear covering or mounting plate removed;

Figure 2 is a vertical sectional View as seen along the line 22 of Figure 1;

Figure 3 is a fragmentary sectional View, on an enlarged scale, as seen along the line 33 of Figure 1;

Figure 4 is a vertical sectional view, on an enlarged scale, as seen along the line 4-4 of Figure 1, certain parts being omitted; and

Figure 5 is an elevation or plan View of one of the parts of the apparatus.

Similar reference characters refer to similar parts throughout the several views of the drawing.

Referring first to Figures 1 and 2, the apparatus or mechanism may comprise any suitable form of frame structure, preferably in the form of a casing which may comprise a box-like .part ID on one side or within which is mounted or housed the electromagnetic mechanism and on the other side or externally of which may be mounted the sounding element, such as a gong II, the mounting being achieved in any suitable way as by means of a screw l2 threaded into a boss l3 secured to or integral with the casing structure [0. The latter is provided With any suitable means, such as a plate l4 preferably of suitably heavy sheet metal by which it may be mounted in position onto a wall or related to an outlet or wall box, and the mounting plate l4 may also function as a closure or cover for the casing structure If], any suitable means such as lugs and screws generally indicated at l5 being provided for effecting detachable assembly of the two.

The casing structure and the gong ll ma be so proportioned that the former is substantially received within the latter as is indicated in Figure 2, and the casing structure IE] is suitably cut away or provided with an opening as at H through which a suitable striker, indicated at l8, may be projected or impacted against the gong II to set the latter in vibration, and it is preferably within the casing structure l0 that the actuating and control mechanism for the striker I8 is mounted and housed.

Preferably, such mechanism comprises a solenoid having a Winding 2| and a core 22 of suitable magnetic material, such as iron or steel, and in such case the striker l8 preferably takes the form of a rod which may be of metal, such as brass, secured in one end of the core 22 in any suitable manner so that the striker rod 18 partakes of the movement to which the core 22 is subjected.

If desired, and preferably, the electromagnetic winding 2! may have associated with it elements of magnetic material, such as iron or steel, to coact with the core 22 to form a magnetic circuit for the flux produced by the winding 2!, the reluctance being variable according to the position of the core relative to the other elements of the magnetic circuit.

Where such an arrangement is employed, I may employ a U-shaped element 23 of iron or steel, having the winding 21 received between its parallel arms 23* and 23 and secured therebetween in any suitable manner, as by a sleeve 24 of non-magnetic material that passes through the winding 2!, and having its connecting arm 23 rest against a support, such as the wall w of the casing structure It to which it may be secured as by screws 25. The element 23 may thus function as a support for the solenoid structure, and where I employ gravity as a means for effecting the return stroke ,of the solenoid core 22 and its striker I8, the support 23 is mounted or secured so as to hold the solenoid 2| with its axis extending upright, as in the drawing. The sleeve 24 preferably also functions as a guide for the Core 22.

Below the solenoid 2! for coaction with the solenoid core 22 in a manner later described, I provide a circuit-controlling mechanism which preferably comprises a suitable support, such as a plate-like member 2'! preferably of insulating material, supported in any suitable manner as by L-shaped brackets 23 and screws or bolts from the wall m of the casing structure H3, and upstanding from the insulating support 21 are two transversely spaced plate members 30 and 3|, preferably of metal and suitably secured to the insulating member 21. Thus they may be L-shaped or be provided with ears or lugs at their lower ends so that they may be securely mounted in upstanding and transversely spaced relation, as by bolts 32 and 33 respectively.

By the upstanding members 3li-3l is supported a flat sheet metal member 34 made of a suitably springy material, such as cop er of suitable hardness, brass, bronze or the like, and it is so supported and proportioned in relation to the spacing between the members 33-4! that it is normally in a slightly bowed condition, whereby it normally strains, or is stressed, to assume either of two positions or conditions in one of which it is bowed downwardly as shown in Figure 1 or is bowed in reverse direct on, or upwardly. Depending upon the material employed, and the dimensions of member 34 or upon the spacing between the members 303I relative to the effective length of the member 34, the transition of the member 34 from one condition to the other, as from the condition of being upwardly concave to a condition of being upwardly convex, or vice versa, takes place with a snap action the intensity of which may be varied according to such factors as those just noted.

A convenient way of mounting the member 34 relative to the upright members 3iJ-3l comprises the provision of ears or tab-like extensions 34 (see Figure at opposite ends of member 34 for reception, respectively, into apertures 35 and 36 (see Figures 2 and 1) provided in the members 3ll-3l, the apertures being preferably sufficiently larger than the cross-sectional dimensions of th tab-like extensions 34 to permit sufiicient play of the latter with respect to the former as the member 34 flexes from ne condition to another. With such a mounting, which facilitates manufacture in that it involves only simple stamping operations, the stress under which the member 34 is put to bow it may be fixed by suitably proportioning the spacing of the members 3ll-3| relative to the effective length of the member 34, that being the longer dimension as seen in Figure 5, exclusive of the tab extensions 34 Preferably I provide also suitable means for limiting the bowing in both directions. Thus I may provide an extension 3% at the upper end of member 30, bent over and downwardly as shown in Figure 1 and of sufficient length to extend toward the middle portion of the member 34, thus to overlie it. If, therefore, the member 34 has applied at or near its center sufiicient force to carry its center beyond the line joining the effective supports at the ends of the member 34, the resultant energy stored in the member 34, aided by other factors as will now be clear, is effective to bow the member 34 upwardly into an upwardly convex condition to an extent limited by its engagement with the stop arm or element 39 Bowing in a downward direction, I prefer to limit by an arm 31 of suitable sheet metal which I preferably make also to serve as a contact element for coaction with the member 34 as later described, and arm 3'! as is better shown in Figure 3 preferably is substantially U-shaped, having one arm 31 extending preferably underneath the insulating plate support 21 to which it is secured as by bolts 38 and having its other arm 3? extending into a position underneath a central portion of the member 34, where the effective movement of member 34 is large. Arm 31 preferably carries a contact point or stud 43, presenting an upwardly extending contact for engagement with a similar contact point or stud 41 mounted or secured in the member 34. These contact elements may be made of any suitable metal or alloy, of kinds known in the art. for better resisting the effects of sparking.

The member 37! may have some degree of springiness though it is preferable that such springiness be small in amount in order not to vary materially the position of its contact element 40 and it is positioned at such a height, as viewed in Figure 3 or Figure 1, that the member 34 does not bow itself in downward direction to its extreme possible position, in order thereby also to have the spring member 34 exert pressure of en agement between its contact element 4! and the contact element 40 of the stop arm 31, thus making for good closure of the circuit controlled by these contact elements.

I next provide a double-acting lost-motion connection between the solenoid core 22 and the member 34 and this may convenientl comprise an aperture 34 in the member 34. preferably at its center (see Figure 5) through which extends a downward extension of the core 22 having thereon vertically spaced enga ing elements 42 and 43. Where the core extension extends through the aperture 34 as in the illustrative construction, elements 42 and 43 are dimensioned so as not to pass through the aperture and they may conveniently comprise washers, as is better shown in Figures 3 and 4, held in spaced relation by a sleeve 44 of the desired axial length, and held assembled to the core 22 as by a screw 45 threaded into a threaded hole in the core 22 and locked against unthreading as by a lock washer 46, a nut 41 threaded onto the screw 45 clamping the elements 42, 44 and 43 against the head of the screw.

With the core 22 in its position of rest as shown in Figure 1, to which it is brought and held, in the illustrative embodiment, by gravity, the weight of the core 22 with the parts carried by it is taken by the member 34 and preferably adds to the pressure of engagement of contact element 4| with contact element 40, it being noted that the stop arm 31 is of sufiicient stiffness or rigidity to resist such pressure and hence to insure maintenance of such pressure of contact.

The contacts 40 and 4| are connected in series with the winding 2|. Thus a suitably insulated conductor 48 connects one terminal or end of the winding 2|, as by one of the bolts 38, to the lower stop or contact arm 31 and hence to contact element 40, and the energizing circuit may be completed by connecting the external circuit conductors to the other end or terminal of the winding 2|, as by conductor 50, and connecting the other external circuit conductor, indicated at 5|, to one of the bolts or screws such as bolt 32, that secures one of the uprights 30 to the insulating support 27, the external circuit comprising a suitable source 52 of electrical energy, either A, C. or D. C., and a suitable switch 53, usually a push button switch.

With the parts in normal position or condition of rest as shown in Figure 1, closure of the circuit as by the switch 53 effects energization of the solenoid winding 2|, and the core 22 starts moving upwardly, element 43 thus moving away from the downwardly bowed member 34, leaving the spring effect of the latter to maintain the circuit closed at contacts 404|. If the solenoid structure has a magnetic circuit, such as member 23 of Figure 2, and of which the core 22 may thus form a movabale part, it will be noted that upward movement of core 22 diminishes the air gap between its upper end and the upper arm 23 thus accelerating the upward motion of core 22 and giving the latter appropriate energy of movement to give the gong the desired impact.

At a suitable point just before the striker I8 hits the gong I the latter thus acting as a stop element to limit motion of the core in that direction, the lower of the spaced engaging elements 42 and 43 engages the underside of member 34, to stress it in upward direction to bring its midpoint above the line connecting the effective supports at the ends of the member 34, and this" action may absorb an amount of energy from the energy of motion of the solenoid that is preferably relatively slight but which if desired may be made of greater magnitude depending upon the factors, such as those above mentioned, attending the construction and relationship of the member 34, its supports, and related parts.

The core 22. having brought the midpoint of the member 34 just above the above-mentioned line, member 34 snaps upwardly with a snap action that may be made of such intensity as may be desired according to the above-mentioned factors, but which is preferably of a low degree of intensity, thus completing its upwardly bowed condition. the core 22 at the same time completing the impact of the gong. In this connection it is to be noted that the upwardly bowed condition of member 34 holds the contacts 4|! and 4| separated and hence holds the circuit open, without aid from the core 22.

The circuit being broken at contacts 404|, core 22 and its related parts start moving downwardly, the upper of the two spaced members 42 and 43 of the lost motion connection approaching the still upwardly bowed member 34 and not engaging it until such time is elapsed as it takes the core 22 to move downwardly by the distance of the spacing of the two spaced elements; such spacing may be on the order of /1" or so, in one illustrative embodiment.

The force returning the core 22 is suificient, upon engagement of the upper spaced element 43 with the member 34, to strain the latter downwardly below the above-mentioned straight line, member 34 thence assuming its downwardly bowed position and with the circuit now again closed at contacts 40--4|, the above-described cycle is repeated for as long as the circuit is held closed by the external control switch 53.

With such an arrangement and with such coactions, I am enabled to achieve a single cycle of relatively long duration and hence achieve, for a given time-length of closure of the main circuit as at the switch 53 a succession of fewer impacts of the gong or other sounding element than is possible with known constructions utilizing make-and-break circuit controlling devices; accordingly, I am enabled to get better audible signaling action and more particularly more efficient sound production, for a given size of sounding element, than is obtainable with such prior constructions where the impacts follow in rapid succession and virtually never give the sounding element time enough between successive impacts to emit its true tone. Particularly with gongs of large size, they are designed or constructed to have nicety and purity of quality for their intended tone, and with my construction the slow-acting mechanism leaves a sufficient time interval between successive impacts for good tone emission and avoids the quick damping action which each succeeding striker blow has upon the vibrating gong where, as in such prior constructions, the blows quickly follow each other.

These actions are also aided in that, though the core 22 actuates the member 34 on the upstroke, at the actual moment of impact of the striker with the sounding element there need not be any spring effect, as in prior constructions, acting upon and opposing the solenoid core or other movable magnetic member, for in my construction the lower element 42 of the lost motion connection need do no more than start the member from its downwardly bowed condition into its upwardly bowed condition, for member 34 can of its own accord complete the last half of such movement of transition without aid from the plunger and a preferred'position of the upper stop member 30 is such that the l mit of upward bowing of member 34 positions the under-surface of the latter slightly above the upper limit of travel of the lower lost motion element 42, that upper limit coinciding with actual physical engagement of the striker IS with the sounding element H.

In the preferred arrangement, the member 34 is comparat vely light and requires little energy to cause it to shift from one bowed condition to the other, and hence may be made quite sensitive if desired; on the other hand, these relations may be varied as may be desired according as such factors as those earlier mentioned above are varied. An advantage also in making the part 34 relat vely light insofar as the energy required to shift its bowed condition is concerned, is that the return force of the plunger, gravity in the illustrative embodiment, can dependably and consistently insure the closure or engagement of contacts 40 and 4! when the device is in its at-rest condition or open-circuited at the switch 53; thereby risk of having the apparatus held opencircuited at the contacts 4il4l can be avoided.

The double-acting lost motion connection moreover will be seen also to delay re-energization of the winding 2| until the core 22 is rather definitely in its lowermost position, a position in relation to the flux of the winding 2| in which the reluctance of the magnetic circuit, whether or not elements like the element 23 are employed, is relatively large, thus achieving an effect somewhat analogous to delayed steam admission to a steam engine cylinder by its valve mechanism, or like a retarded spark adjustment for an internal combustion engine as contrasted with an advanced spark adjustment.

The construction, moreover, is capable of ease and dependability of setting or adjustment; thus the elements 30 and 37 (Figures 1 and 3) can be easily and quickly adjusted as by bending them to fix as may be desired the upper and lower limits of bowing of the member 34; and the upstanding supporting members 3il3l, preferably made of a suitable sheet metal, may likewise be readily adjusted, as by bending, to set the spacing between them in reference to the member 34. Desirably, also, I may make these members 3il-3l of material having a suitable degree of springiness or resiliency and thus cause them to coact materially in effecting transition of member 34 from its intermediate substantially straight line condition to bowed condition.

Thus, for example, spacing between members 30 and 3! at the points of support of member 34 may be less than the straight line dimension of member 34, but with springiness in the members Bit-35, the latter can spread apart as the member 36 is strained from one bowed condition to its straight line or middle condition, in effect and thereby storing energy in the members 393I, that energy being thereafter expended in bowing the member 34 into its bowed condition in opposite direction.

It will, therefore, be seen that the actions above described and the factors above mentioned as capable of affecting that action, may include one or bothstructural and functional features, as follows: A self-biasing action by member 3% alone, into either of its two bowed conditions, may be effected with relatively fixed spacing between the members 3il3| in which case the latter may have little or no yieldability and the member 34, x

at its middle position, would partake of a nonstraight lin form and would preferably be relatively light. Here there would be storage of energy in the resultant somewhat distorted or nonstraight line intermediate condition of the member 34, the energy being expended to insure transition to its bowed condition in opposite direction. Or, the self-b asing action may be achieved, as above indicated, by a spring effect given to the members 3fl3l. to such an extent as always to bias them into positions where the spacing is less than the straight line length of member so that movement of member 34 into middle or straight-line condition stresses the members 30-4! in directions away from each other, thus storing energy in them for expenditure to insure the transition of member 3d into bowed condition in opposite direction.

In either case, or in the case of the combination of both such structural and functional features, it will be seen that the resultant mechanism for controlling the contact elements 40-- 41 operates reversibly and in effect in two successive stages, one of which is a starting stage in the course of which the moving core need only move the member 34 to its middle position, whence follows the succeeding stage which, upon the expenditure of the stored energy as above described, the mechanism is in effect self-actuating.

Thus it will be seen that there has been provided in this invention a signaling apparatus in which the various objects above mentioned together with many thoroughly practical advantages are successfully achieved. It will be seen that the mechanism is composed of parts easy to manufacture and easy to assemble, is easy to adjust as, for example, by suitably bending or setting the stop elements 39 and 31, can be embodied in compact form, and is capable of achieving, whether energized by A. C. or D. C., slowly recurring impacts, thus making for nicety and eificiency of tone production.

As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying rawing is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. A signaling apparatus comprising a sound ing element, a solenoid having a winding and a reciprocable core with striker means to impact said sounding element upon movement of the core in one direction, and means for causing said striker means to impact said sounding element in slow succession, to thereby delay damping of the vibrations of said sounding element by succeeding impacts, said means comprising a flat spring element, two supports spaced apart by a distance less than the length of said spring element for supporting the latter at its ends, whereby said spring element may be reversibly bowed and is tensioned to hold itself in either of its bowed positions, contact means controlled by said spring element and being in circuit with said winding and being closed in one of said bowed positions and open in the other, and means forming a lost motion connection between said core and said spring element to interpose a time interval of delay during each stroke of said core before said core is effective to reversely bow said spring element.

2. A signaling apparatus comprising a sounding element, a winding, a striker having delayed action actuating means therefor that comprise a movable member biased in a direction away from said sounding element and movable in response to energization of said winding in a direction to effect an impact of said element by said striker, spring means capable of assuming either of two self-biasing positions, contact means controlled by said spring means and in circuit with said winding, said contact means being closed in one of said self-biasing positions of said spring means and being open in the other, and means forming reversibly-acting lost motion connection between said member and said spring means for interposing during each stroke of said member a time interval before said member is effective to actuate said spring means.

3. A signaling apparatus comprising a sounding element and a member having means mounting it for reciprocation in a substantially fixed length of stroke into and out of impacting engagement with said sounding element and being normally biased in one direction, and means for causing said member to impact said sounding element in slow succession, to thereby delay damping of the vibrations of said sounding element by succeeding impacts, said means comprising energizable electromagnetic means for moving said member in opposite direction, makeand-break contact means for said electromagnetic means constructed and operating in either make or break direction in two operational stages, one of which is a starting stage requiring the application thereto of energy and the other of which is a self-actuating stage of completion of actuation, and means operating during each stroke of said member to apply energy to said make-and-break means for said starting stage.

4. A signaling apparatus comprising a sounding element and a member having means mounting it for reciprocation in a substantially fixed length of stroke into and out of impacting engagement with said sounding element and being normally biased in one direction, and means for causing said member to impact said sounding element in slow succession, to thereby delay damping of the vibrations of said sounding element by succeeding impacts, said means comprising energizable electromagnetic means for moving said member in opposite direction, makeand-break contact means for said electromagnetic means constructed and operating in either make or break direction in two operational stages, one of which is a starting stage requiring the application thereto of energy and the other of which is a self-actuating stage of completion of actuation, and lost motion connection means between said member and said make and break means to apply to the latter during each stroke of said member energy for said starting stage thereof and by the operation of said lost motion connection means to interpose a time interval during each stroke of said member before the latter can apply energy to said make-and-break contact means.

5. A signaling apparatus comprising a sounding element, a solenoid having a winding and a reciprocable core with striker means to impact said sounding element upon movement of the core in one direction, a flat spring element, two supports spaced apart by a distance less than the length of said spring element, for supporting the latter at its ends, whereby said spring element may be reversibly bowed and is tensioned to hold itself in either of its bowed positions, means forming a lost motion connection between said core and said spring element, an arm limiting bowing of said spring element in one direction, and circuit controlling means in circuit with said winding comprising a contact means m0vable in response to bowing of said spring element and a contact means coacting therewith and limiting bowing of said spring element in opposite direction.

6. A signaling apparatus as claimed in claim 5, in which said lost motion connection comprises an aperture in said spring element, a sleeve of insulating material exending through said aperture and having insulating shoulder means at its ends, and a stud extending through said sleeve and carried by said core.

7. A construction as claimed in claim 5, in which at least one of said two supports is bendable and capable of being forcibly bent to determine the distance between said two supports and hence the tension with which said spring bows from one position to the other.

8. A signaling apparatus as claimed in claim 5, in which said arm is bendable and may be p0 sitioned by forcibly bending it to vary its limiting action upon said spring element, there being means for adjustably supporting one of said contact means to determine at will the limiting action of said contact means when said spring element bows in opposite direction.

GEORGE R. FISH.

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