US3187230A - Electric reset gravity drop adapted for use in annunciators - Google Patents

Description

June 1965 T. e. BRISTOVISH 9 3 ELECTRIC RESET GRAVITY DROP ADAPTED FOR USE IN ANNUNCIATORS Filed May 26, 1959 3 Sheets-Sheet 1 INVEN TOR. THOMAS G. BRISTOVISH A TTORNEYS.

June 1, 1965 T. e. BRISTOVISH CIATORS ELECTRIC RESET GRAVITY DROP ADAPTED FOR USE IN ANNUN 3 Sheets-Sheet 2 Filed May 26, 1959 FIG. 6.

FIG. 5.

w w M FIG. 8.

FIG.7.

INVENTOR. THOMAS G. BRISTOVISH a Fab ATTORNEYS.

June 1, 1965 T. e. BRISTOVISH 3,187,230

ELECTRIC RESET GRAVITY DROP ADAPTED FOR USE IN ANNUNCIATORS 3 Sheets-Sheet 3 Filed May 26, 1959 INVENTOR. THOMAS G. BRISTOVISH 6) Wm F ATTORNEYS United States Patent M 3,187,230 ELECTRIC RESET GRAVITY DROP ADAPTEI) FOR USE IN ANNUNCIATORS Thomas G. Bristovish, Norwaik, Conn, assignor to Edwards Company, Incorporated, a corporation of New York Filed May 26, 1959, Ser. No. 815,860 9 Claims. (Cl. 317137) Annunciators which respond to the closing of an electric circuit by giving a signal which directs attention to a particular place are in widespread use today as for example in manufacturing plants for signaling a change in operation or failure of equipment and in institutions, homes and offices for summoning a nurse, secretary, maid or the like.

In the type of annunciator to which this invention relates a gravity drop shutter is held in locked position until the feed circuit to the annunciator is closed to actuate a coil which attracts an armature that releases the shutter so that it will drop down under the influence of gravity and give the required signal. In order to reset the shutter electrically by remote control means, separate coils are required to operate a mechanical device which will reset all of the shutters simultaneously. In those cases where it is desirable to reset the individual shutters a separate coil is required for each shutter. The coils for resetting the shutters are expensive and materially add to the cost of the unit and the coils take up room which is a drawback in some installations where size is an important factor.

In accordance with the present invention there has now been devised an electromagnetic device which employs a single coil adapted to reset as well as release the gravity drop shutters in the annunciator. In the simplest form of invention a coil is wired into two separate feed circuits one of which includes an indicator switch and the other a reset switch. The gravity drop shutter is provided with a contact which controls the circuits and depending upon the position of the shutter the circuit through the coil may be closed either by the indicator switch or by the reset switch. When the circuit is closed by the indicator switch an armature is attracted to the coil to release the shutter and as the shutter falls into signaling position under the influence of gravity it opens the circuit through the indicator switch. When the signal on the annunciator is to be erased the reset switch is closed so that the coil will again attract the armature and by means of a simple mechanical coupling the armature causes the gravity drop shutter to return to the initial starting position. In moving into the initial starting position the shutter opens the circuit through the reset switch and prepares the circuit through the indicator switch so that it may be closed by such switch.

The use of a single coil to actuate a prime mover and cause the gravity drop shutter to move in two di'lferent directions to release and then return to starting position makes it possible to use a very simple construction which is inexpensive to manufacture and install in the limited space available in an annunciator box. The electromagnetic device of the present invention gives positive reli-.

able action and while it is particularly useful for resetting the gravity drop in an annunciator if desired the device may be employed in place of the conventional relays now in use.

Further details and advantages of the present invention may be readily understood by reference to the accompanying drawings in which:

FIG. 1 is a side view of one form of electromagnetic device of the present invention held in initial starting position.

FIG. 2 is a front View of the device of FIG. 1.

FIG. 3 shows the device of FIG. 1 with the shutter down in signaling position.

FIG. 4 illustrates one of the many possible circuits in which the device of the present invention may be used.

FIGS. 5 and 6 illustrate a second form of the device of FIG. 1 and the circuit employed for operating such device.

FIGS. 7 and 8 illustrate a third form of the device of FIG. 1.

FIGS. 9, 10 and 11 illustrate a fourth form of the device of FIG. 1.

FIG. 12 is a top view illustrating a fifth form of the device of FIG. 1.

A preferred form of the electromagnetic device 10 of the present invention is shown in FIG. 1. The device comprises a conventional coil 12 having a core 13 surrounded by the usual winding. The coil is mounted in fixed position on a support framework 14 which pivotally mounts an armature or prime mover 16 by means of a pin 17 so that the top portion of the armature above the pivot will be attracted in against the coil. A spring such as leaf spring 13 which is mounted in fixed position on the armature 16 bears against the face of the coil and constantly urges the top portion of the armature to pivot away from the coil. Movement of the armature away from the coil is limited by a stop 29 which is mounted on framework 14 in position to bear against the bottom portion of the armature below the pivot and hold the armature upright in starting postion as shown in FIG. 1.

A gravity drop shutter or circuit control member 22 which in the preferred embodiment includes two side walls 24 joined together by a front wall 26 is pivotally mounted at the base of the side walls in framework 14 as at 28. Shutter 22 is free to pivot downwardly under the influence of gravity until the side walls 24 hit against pin 17 which serves as a stop to hold the front wall 26 of shutter 22 in position in front of a window in the face of the annunciator box (not shown). Shutter 22 is held up in its initial starting position shown in FIG. 1 by means of a small flange 30 which constitutes a latch member on armature 16 which fits under a cooperative flange 32 that projects out from the inside surface of the front wall 26 of the shutter to support the shutter and hold it up in its initial starting position. It can now be understood that when coil 12 is excited it attracts the armature which pivots against the coil to withdraw flange 30 out from under flange 32 so that the shutter is free to pivot downwardly under the influence of gravity. In FIG. 3 the shutter is shown in the down position with the side walls 24 resting against stop 17.

In accordance with the present invention a mechanical coupling is provided between the armature and shutter so that the shutter will be restored to its initial starting position when the armature is again attracted by the coil. To this end coil 12 is provided with a pin 34 which is slidably mounted in the coil to hear at one end against the leaf spring 18 of armature 16. The second end of the pin bears against a flange member 36 mounted in fixed position on the base of the shutter. Since flange member 36 is mounted on the opposite side of pivotal point 28 from the front wall 25 of the shutter, the front wall and the flange 36 will move in opposite directions when the shutter rotates on its pivotal point 28. With this construction when armature 16 is drawn in against the coil, the armature will push against pin 34 and move it over to the left (FIG. 3) and the pin will in turn push against flange 36 to rotate the flange counterclockwise around pivotal point 28. As a result the gravity drop shutter 22 will move up into its initial starting position.

Detailed operation of the electromagnetic device of the present invention may be readily understood by reference to FIG. 4 which illustrates one example of the many circuits in which the device may be used. It will be under- Patented June 1, 1965 stood that the circuit shown in FIG. 4 is merely chosen for the purpose of illustration and use of the electromagnetic device is not limited to the circuit or to the purposes for which it is employed in such circuit. The circuit shown in FIG. 4 may be used to give an audible as well as visual signal. The details of the construction of the electromagnetic devices 1d are not shown in FIG. 4 to better illustrate the circuit and electrical control of the device.

Three electromagnetic devices lilA, B and C of the present invention are mounted in position behind the window of an annunciator box (not shown) so that when the gravity drop shutters are released from the initial starting position a visual signal will appear in the window to direct attention to a particular place. Electrical current is supplied to the coil 12 of each device ltl from the feed line 38 by means of a conductor ltland indicator switch 42. Conductor til is connected to one of two spaced spring type contacts 44- and these contacts are closed by a third contact 46 carried on but insulated from a pin 48 mounted in fixed position in the side wall 24 of the gravity drop shutter (see FIG. 2). When the gravity drop shutter is up in its initial starting position (FIG. 1)

the spring contacts 44 are closed as shown in FIG. 4 but the indicator switch 42 is open and no current will flow through the coil 12. Spring contacts 44 are connected to the winding of coil 12 by conductor 50 so that the current may flow through the coil into conductor 52 which is a common conductor that connects the coils in series with a fourth electromagnetic device ltl-D that controls an audible signal such as bell 54. Bell 54 is wired in a separate circuit 55 later described. The current from coil 12 of llilJ-D flows out through a resistance 56 positioned in the conductor 58 which terminates the circuit through the coils.

In operation when any one of the indicator switches 42 is closed as by failure of a turbine or by a thermostat in case of fire, current will flow through the coil 12 of the closed indicator switch (as for example through the coil of device 1t)A) and through the coil of device ltl-D and resistor 56. The turns of coil lit-D and resistance 56 are. so balanced against the current and the resistance of the coils of the devices iii-A, B and C that the armature of device lD will be immediately attracted to the coil to release the gravity drop shutter of device MLD. When the shutter falls down under the influence of gravity con tact are on the pin 48 will close the gap of the spring type contacts 62 to close the separate circuit 55 and set off the alarm bell. At the same time contact 64 carried on a pin 66 mounted in the opposite side wall of the gravity drop shutter of device Ill-D will close the gap in the spring type contacts 68 of connector 7t) which short circuits the current around the device lit-D and resistance As a result the current through the coil of device 1-A is now strong enough to generate the necessary magnetic force to attract the armature over against the coil so that the gravity drop shutter is released from its initial starting position (FIG. 1). As soon as the gravity drop shutter of the device lilA starts to drop contact 46 opens the gap between the spring contacts 44 and armature 16 is pushed away from the face of the coil 12 by spring 18 into its starting position in spaced relationship to the face of the coil. At the same time pin 34 is pushed to the right towards the armature by flange 36. If the circuit through the coil of device ltlA were not opened the armature would remain against the face of the coil and the shutter could not fall all the way down to rest against stop 17 because the pin 34 would not be free to move to the right (FIG. 1) and as a result the pin would prevent the shutter from dropping down into full signaling position. When the shutter is down it provides a visible signal in the face of the annunciator box to indicate the place where help is needed. If a second source of trouble develops the indicator switch of either device 4; M43 or lib-C will close and a second visual signal will be given.

Alarm bell 54 is still ringing and the operator may wish to turn oif the alarm while attending to the trouble which caused device lilA to signal. In such case it is only necessary to close the reset switch '72 in order to restore the gravity drop shutter of device lit-D to its initial starting position. Switch '72 is a composite switch so that when this switch is closed it automatically opens switch 71 in connector 79 (FIG, 4) so that the short circuit is broken and current will flow from the feed line 35 through the coil or" device ll@D. When switch 72 is open the switch 71 is automatically closed. The current flows to the coil of device lid-D and flows through connector '73 and the spring type contacts 74 which were automatically closed by contact 76 when the shutter of device ltlD dropped down to set oif the audible alarm. When coil 12 of device ltl-D is excited by closing reset switch '72 the armature of device 1ii'D will be pulled over against the face of the coil and the force of the blow will drive pin 34 over to the left (FlG. 3) againstfiange 36 to pivot the gravity drop shutter up into its initial starting position. As soon as the gravity drop shutter starts to move up into initial starting position contact 76 opens the gap between spring contacts '74 and the armature is urged away from the face of coil 12 by means of spring 18 so that the'fiange 30 will ride along the surface of the inside of wall 26 of the shutter until it hits flange 32 which is positioned at an angle relative to the surface of flange 36 so that flange 3i can pass flange 32 and move in under flange 32 to hold the shutter up in its initial starting position. A stop 78 is mounted on framework 14 (FIG. 1) in position to contact the side wall 24 of the shutter and limit the travel of the shutter. Stop Ztl limits the travel of the armature and holds it in' positionwhere it will support the shutter and be attracted to the coil when an indicator switch is closed, Restoring the drop shutter of device llil-D will not restore the shutter of devices lltlA, B and C which continue to give a visual signal.

As described hereinabove before when an indicator switch 42 is closed the shutter of device iii-A will drop down and as the shutter descends it opens the gap of contacts 44 and when the shutter reaches signaling position contact 80 of pin 48 will close the gap between spring contacts 32. The shutters of devices MFA, B and C may be restored to initial starting position by closing the reset switch 83. Reset switch 83 is a composite switch and when switch 83 is closed it automatically closes switch 84 which completes the short circuit of conductor 85 so that the current of conductor 52 will bypass the coil of devices lit-D. When switch 83 is closed current will flow through the coils of those devices that have a shutter in signaling position and restoration of the shutters of devices T.-A, B and C will take place in the manner described for device 1594). When switch 83 is opened switch 84 isautomatically opened to break the short circuit of conductor 35' so that it does not interfere with operation of device lit-D. If desired each of the devices 1tlA, B and C may be provided with'a separate reset switch (not shown) and in such case each individual device may be reset independently of the other devices.

Having explained the detailed operation of the device it will now be understood by those in the art that the exact construction of the devices described need not be employed to utilize the principle of operation. For example any desirab'le form of simple circuit control member such as a rocker arm may be pivotally mounted in cooperating relationship with the armature of the coil in place of the shutter and it is not necessary to have a pin slidably mounted in the coil for restoring the rocker arm as any convenient form of mechanical coupling between the armature and coil may be employed for this purpose, For example the flange 36 may be turned down and'then connected to the armature below the pivot so that the armature will pull the flange down and thereby restore the shutter to its initial starting position. 'It will also be apparent to those skilled in the art that the electromagnetic device of the present invent-ion need not be used in an annunciator circuit and that the device is useful as a relay as illustrated in connection with the use of the device -13. It is also apparent that any number of contacts may be carried by the gravity drop shutter to operate a multitude of auxiliary independent circuits. While the contacts carried by the shutter are useful in certain applications in other applications in which space is limited the contacts have the decided drawback of expanding the width of the space required for each electromagnetic device.

This problem may be overcome by means of the form of contact shown in FIG. 5. As there shown the electromagnetic device 10 is identical with the device shown in FIG. 1 with the exception that the shutter 22 does not carry the contacts for controlling the current supplied to the coil. In this modified form of the invention the contacts 86 are positioned behind the electromagnetic device 10 and the contacts do not expand the width of the device. Contacts 86 are conventional C type make and break contacts comprising a center spring contact 38 which feeds current to the coil as illustrated in FIG. 6. When shutter 22 is up in its initial starting position flange 36 presses the contact 88 against the spring contact 90 which connects the coil to an indicator switch 92 in the current feed line. As a result when the indicator switch is closed coil 12 is excited to pull armature 16 in against the coil and release the shutter which will fall down under the influence of gravity to give a visual signal. In dropping down flange 36 releases spring con-tact 88 which is under tension to move over into contact with the spring contact 94. This connects coil 12 with the reset switch 96 and when switch 96 is closed the shutter will be returned to its initial starting position and flange 36 will again press contact e8 against contact 90. In the form of device shown in FIG. 5 flange 36 will of course be insulated from the body of the shutter. If desired a plurality of contacts 86 may be controlled by shutter 22 for operating auxiliary circuits. Such construction is illustrated in FIGS. 7 and 8. As there shown shutter 22 is provided with an extension arm 98 which carries a contact actuating device such as roll 1% of nylon or other non-conductive material which is adapted to open and close a plurality of contacts as indicated at 102 in FIGS. 7 and 8. The individual contacts will of course be opened or closed depending upon the position of the shutter.

A particularly unique construction for the control of contacts is illustrated in FIGS. 9 through 11. As there shown the spring contacts 104, 196 and 168 each have two spring legs 11d and 1 12 respectively and the contacts are located in position to be operated by shutter 22 of the electromagnetic device which is of identical construction with the device shown in FIG. 1 with the exception that the shutter'is provided with an extension arm 114- which mounts a pair of spaced rolls 116 and M8. When shutter 22 is up in its initial starting position (see FIG. 10 which is a bottom view of FIG. 9) roll 112 bears against one of the two springs of each contact and depending upon the length of the spring the circuit of the contact will be closed or opened. Referring to FIGS. 9 and 10 it will be seen that the spring contacts are so arranged that when shutter 22 is up in its initial starting position spring contact 1&4 is open. When armature 16 is pulled over against the face of the coil the shutter will drop down into signalling position whereupon spring contact 166 will be open and spring contact 1% will be closed. As the shutter drops down spring contact 104 will close and then open when the second roll 118 of the shutter contacts leaf spring 112 to again open the con-tact 194 when the shutter reaches signaling position as shown in FIG. 11. In this way shutter 22 in moving from its initial starting position to its signaling position will cause contact 194 to make and then break the circuit of the contact and the same is true when the shutter is restored to its initial starting position. The construction and control of contacts shown in the drawings provides great flexibility in the control of electric circuits and as a result the control of electromagnetic device 10 may be used in a wide variety of applications for controlling a multitude of auxiliary circuits.

Further modifications and applications of the electromagnetic device of the present invention will be obvious to those in the art. In some applications it may be desirable to mount the electromagnetic device with the shutter in position to pivot in a horizontal plane as illustrated in FIG. 12 of the drawings. In such case a spring 126 may be employed in conjunction with the armature for operating the shutter. Spring is attached to the shutter so that the spring will be under tension when the shutter is in its initial starting position and as a result when the shutter is released by the armature, spring 120 will pull the shutter over into signaling position and thereafter the shutter will be restored to its initial starting position against the tension of spring 120 when the reset circuit is closed.

It will be understood that it is intended to cover all changes and modifications of the preferred embodiment of the invention herein chosen for the purpose of illustration which do not constitute departures from the spirit and scope of the invention.

What I claim is:

1. An electromagnetic device for use in an annunciator comprising an armature, spring means tensioned to hold the armature in a starting position, electromagnetic means for generating a magnetic force on the armature, to overcome the force of said spring means to move said armature out of its starting position when said electromagnetic means is actuated to generate a magnetic force on the armature, a gravity drop circuit control member adapted to move under the effect of gravity between a raised starting position and a lower signaling position, said armature when in its starting position being adapted to hold the circuit control member in the raised starting position and to release said circuit control member when a magnetic force is generated to change the position of the armature so that the circuit control member will be free of the armature so that it can move under the effect of gravity into a signaling position in the annunciator, a mechanical coupling between the armature and circuit control member which is adapted to force the circuit control member out of signaling position and back into starting position when an electromagnetic force is generated to cause the armature to change position.

2. A structure as specified in claim 1 which includes a contact member controlled by said circuit control member to open and close an electric circuit when the circuit control member moves from one into the second of said positions.

3. An electromagnetic device for use in an annunciator comprising electromagnetic means for generating a magnetic force, an armature pivotally mounted in position to be attracted by said magnetic force and pivot relative to its mounting, spring means tensioned to urge the armature away from the electromagnetic means into a starting position, a circuit control member pivotally mounted in position to be controlled by said armature, said circuit control member being adapted to pivot between a raised starting position and a lower signaling position in the annunciator, releasable latch means carried by said armature, said releasable latch means being operable to engage and hold the circuit control member in the raised starting position and to release said circuit control member when the armature is caused to pivot out of its starting position, whereby when the armature is attached by the electromagnetic control means the circuit control member will be released to pivot from the raised starting position into the lower signaling position in the annunciator, a

mechanical couplingbetween the armature and circuit control member which is adapted to force the circuit control member out of signaling position and back into the initial starting position when an electromagnetic force is generated to cause the armature to pivot out of starting position.

4. A structure as specified in claim 3 in which the mechanical coupling comprises a pin slidably mounted in position between the armature and the circuit control member which pin is adapted to be forced against the circuit control member to rotate it out of signaling posiion and up into initial starting position when an electromagnetic force is generated to cause the armature to change position.

5. In an electromagnetic device of the type which includes a winding for generating a magnetic forceto attract an armature to one end thereof and release a circuit control member which thereupon pivots from an initial starting position into a second position, the improvement which comprises a mechanical coupling between the armature and circuit control member which includes a pivot arm member attached to the circuit control member and facing the end of the coil away from the armature and a shaft means slidably supported in the winding and adapted to be engaged by the pivot arm member when the control member is moving from its initial starting position into its second position so as to slide the shaft means in the coil towards the armature and adapted to be forced by the armature against the pivot arm member to force the circuit controlling member out of the second position back into the initial starting position when the armature is attracted by the winding.

6. An electromagnetic device comprising a winding for generating a magnetic field, a first electric circuit for supplying current to the winding, a second electric circuit for supplying current to the winding, an armature, yieldable means for holding the armature within the confines or" the area of said magnetic field in position spaced away from said winding, said armature being adapted to move out of said position towards the winding when a magnetic field is generated by the winding and to move back into position spaced away from the winding when both circuits for supplying current to the winding are open, a gravity drop circuit control member, means for pivotally mounting a circuit control member, said means being positioned at a point between opposite end portions of the circuit control member whereby when the circuit control member is caused to pivot opposite end portions will move in different directions, said armature being adapted to hold the circuit control member in an initial starting position when the armature is in position spaced away from said winding and to release said circuit control member when the armature is moved out of said position towards the winding so that the circuit control member will be free to pivot and drop down under the influence of S for coupling the armature with the said end portion of the circuit control memberwhich means are adapted to pivot such end portion of the circuit control member and move the circuit control member from the second position into the initial starting position when the armature is forced by the magnetic field to move towards the Winding, a first open switch positioned in the first circuit, a second open switch positioned in the second circuit whereby when one of the said switches are closed the armature will be attracted to the Winding to cause the circuit control member to change its position and whereby the circuit control member in changing position will open the electric circuit closed by the switch and prepare the other one of said electric circuits so that it may be closed by the switch.

7. A structure as specified in claim 6 in which the means for coupling the armature with the circuit control member comprises a pin slidably mounted in position to be pressed against one end portion of the circuit control member by the armature to cause the circuit control member by the armature to cause the circuit control memher to be pivoted from the second position into the initial starting position when the armature is attracted to the winding and said pin being adapted to be moved by the circuit control member towards the armature when the circuit control member pivots under the influence of gravity from the initial starting position into the second position.

8. A structure as specified in claim 6 in which the means for opening and closing the electric circuits for supplying current to the winding include a flange positioned on one end portion of the circuit control member, a spring contact adapted to close one of said circuits when the spring contact is in a first position and to close the other one of the said circuits when the spring contact is in a second position and said flange being adapted to cause the spring contact to change from one position into the other when the circuit control member changes position.

9. A structure as specified in claim 6 in which the means for opening and closing the circuits include two contact actuating members mounted in spaced position on one end portion of the circuit control member, a make and break spring contact adapted to be contacted by both of said actuating members when the circuit control member changes position.

References Eite-tl by the Examiner UNITED ST ATES PATENTS 545,069 8/95 Galbraith 340-371 959,194 5/10 Auth 340-376 973,676 10/10 Lungen 340-376 1,475,594 11/23 Pierce 340-286 1,526,494 2/25 Henschel 340-376 1,855,804 4/32 Lucas 200-87 2,052,751 9/36 Carbonara 340-371 2,408,106 9/46 Stearn 340-376 2,531,838 11/50 Bergemann 200-87 2,682,585 6/54 Knapp 200-104 2,889,427 6/59 Freedman 200-104 NEIL C. READ, Primary Examiner.

BENNETT G. MlLLER, ROBERT H. ROSE,

Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,187,230 June 1, 1965 Thomas G. Bristovish It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected belo' Column 6, line 72, for "attached" read attracted column 8, line 18, beginning with "of the circuit" strike out all to and including "to be pivoted" in line 21, same column 8, and insert instead of the circuit control member by the armature to cause the circuit control member to be pivoted Signed and sealed this 23rd day of November 1965.

EAL)

ilest:

RNEST W. SWIDER EDWARD J. BRENNER testing Officer Commissioner of Patents

Claims (1)

1. 6. AN ELECTROMAGNETIC DEVICE COMPRISING A WINDING FOR GENERATING A MAGNETIC FIELD, A FIRST ELECTRIC CIRCUIT FOR SUPPLYING CURRENT TO THE WINDING, A SECOND ELECTRIC CIRCUIT FOR SUPPLYING CURRENT TO THE WINDING, AN ARMATURE, YIELDABLE MEANS FOR HOLDING THE ARMATURE WITHIN THE CONFINES OF THE AREA OF SAID MAGNETIC FIELD IN POSITION SPACED AWAY FROM SAID WINDING, SAID ARMATURE BEING ADAPTED TO MOVE OUT OF SAID POSITION TOWARDS THE WINDING WHEN A MAGNECTIC FIELD IS GENERATED BY THE WINDING AND TO MOVE BACK INTO POSITION SPACED AWAY FROM THE WINDING WHEN BOTH CIRCUITS FOR SUPPLYING CURRENT TO THE WINDING ARE OPEN, A GRAVITY DROP CIRCUIT CONTROL MEMBER, MEANS FOR PIVOTALLY MOUNTING A CIRCUIT CONTROL MEMBER, SAID MEANS BEING POSITIONED AT A POINT BETWEEN OPPOSITE END PORTIONS OF THE CIRCUIT CONTROL MEMBER WHEREBY WHEN THE CIRCUIT CONTROL MEMBER IS CAUSED TO PIVOT OPPOSITE END PORTIONS WILL MOVE IN DIFFERENT DIRECTIONS, SAID ARMATURE BEING ADAPTED TO HOLD THE CIRCUIT CONTROL MEMBER IN AN INITIAL STARTING POSITION WHEN THE ARMATURE IS IN POSITION SPACED AWAY FROM SAID WINDING AND TO RELEASE SAID CIRCUIT CONTROL MEMBER WHEN THE ARMATURE IS MOVED OUT OF SAID POSITION TOWARDS THE WINDING SO THAT THE CIRCUIT CONTROL MEMBER WILL BE FREE TO PIVOT AND DROP DOWN UNDER THE INFLUENCE OF GRAVITY INTO A SECOND POSITION, MEANS CONTROLLED BY SAID

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