US1805196A - Automatic brake relay - Google Patents

Description

y 1931- P. D. TARDIFF 0 ,196

AUTOMATIC BRAKE RELAY Filed March .3, 1926 INVENTOR,

PHILLIFD.TARDIF F Patented May 12, 1931 UNITED STATES PHILIP D. TABDIFF, OF DETROIT, MICHIGAN AUTOMATIC BRAKE RELAY Application filed March 3, 1926. Serial No. 91,966.

My invention relates to a new and useful improvement in an automatic brake relay and has for its object the provision of an automatically operated mechanism adapted for use with electrically operated elevators whereby said elevators may be rendered more safe for the occupants thereof.

With electrically operated elevators as now manufactured provision is made that when the control switches of the elevators are opened the brakes will be automatically set so that when the gates are opened and the passengers are entering or leaving the elevator the danger of the elevator starting is supposed to be prevented.

Experience has shown however that in such elevators accidents may happen andinjury inflicted upon the passengers through the starting of the elevator while the gates are opened. A common cause of this is an arcing over at the control switches of the elevator which would release the brake controls and permit the elevator to move either upwardly or downwardly. Another reason for this is defective insulation or broken insulation.

In the present invention I have provided an auxiliary safety device whereby, so long as a circuit is complete through the brake coil it is impossible for the operator to open the gates to permit the passengers either to leave or enter. To effect this I have provided an automatic relay.

The advantages and objects of the invention will further appear as the description proceeds.

The invention consists in the combination and arrangement of parts hereinafter deand only those features which are necessary for the proper illustration of the present invention have been pointed out in this specification.

In Fig. 1 I have shown the positive wire 9 through which the current passes and the negative wire 32. The wire 9 is connected through the wire 10 to a potential switch 11 which may be mounted upon the board and controlled therefrom. The wire 10 is connected through the potential switch 11 to the elevator control switches 12 and 13 each of which co-operates with an auxiliary control switch 12 and 13 positioned between which is a resistance 14. The resistance is connected by the wire 15 to the brake coil 16 and thence to the wire 32, the auxiliary potential switch 17, which may also be postioned upon the switch board being interposed in this connection. The wire 15 is connected through the resistance 18 and the fuse 19 to one end of the magnetic coil 20-the other end being connected by the wire 21 and through the switch 17 to the feed wire 32. The core 22 of this electric magnet is provided with a cross-head for closing the circuit through the contacts 23 and 27the contact 23 being connected through the resistance 26 and the fuse by means of the wire 24 to the positive feed wire 9. The contact 27 is connected through the operating gate switch 28 which is positioned in the elevator cage to the motor 29 which is used for opening and closing the elevator gates. The wire 31 connects through the emergency switch which is positioned in the cage to the motor 29-the construction is such that the current when either of the switches 12 or 13 is closed passes through the brake coil 16 and energizes the electro magnet 20 so as to break the circuit between the contacts 27 and 23. The auxiliary potential switch 17 of course being closed at this time.

When such an arrangement is effected a closing of the switch 28 will not effect a closing through the motor 29 so that the gates of the elevator cage cannot be opened by means of themotor 29. Upon opening of the switches 12 nd 1.3 whi h contr the elevatol by a suitable wire to the armature, the circuit between the contacts 27 and 23 will be closed and it'is only when the switches 13 and 12 are openedthat is only when no current is passing through the coil 20 that negative teed wire 43. The wire 33 is connected through the wire 34 and the potential switch 35 and through the elevator control switches 36 and 37, 36 and 37, the resistance 38 and the wire 39 to the brake coil 40 which is also connected to the negative feed .wire by means of the wire 44 through auxiliary switch 44. The wire 39 is connected by the wire 41 toa contact 42. The wire 43 is connected by means of the wire45 to the automatic gate switch 46, this gate switch comprising an extra contact on the inside of the car gate and being normally closed when the gate is half open.

One of the contacts of the gate switch 46 is connected by the wire 47to the contact 48- a knife blade switch 49 serving to engage the contacts 42 and 48 so as tov control the circuit between the lines 47 and 58 and the lines 41 and 51. This switch 49 may be termed an emergency brake switch or an emergency relay disabling switch and is to be opened only in case of inoperativeness 01". the relays, or failure to function for any reason.

The contact 52 is connected to the wire 51 and the resistance 50 which connects with a fuse. The wire 51is also connected through the wire and the resistance 54 to the contact 55. The contact 57 is connected by means of the wire 56 to the wire 58 which connects with a fuse and a resistance 59 and also the means or the wire 69 to the negative feed wire 43a fuse 70 being interposed in this wire 69. The core 71 of the relay carries a cross head 72 adapted upon movement in one direction for opening a circuit between the contacts 7 3 and 74 which are suitably wired to the gate controls. A secondary cross-head 75 is mounted on the core 71 and adapted-for closing a circuit between the contacts 76 and 57. The contact 76 being connected by the wire 7 7 to the relay 78. This relay being connected by the wire 7 9 through the resistance 80 and the fuse 81 and the wire 82 to the positive feed wire 33; The core 83 of the relay 7 8 carries a cross head 84 adapted upon movement in one direction for closing the circuit between the contact 85 which is suitably grounded and the contact 55.

The operation of the device is such that the safety desired is obtained in an electrically operated elevator of this class. The switch 46 is normally open, and as previously stated, it is closed when the gates are moved to partly open position. When the switch 49 is closed and the switch 46 isclosed by opening of the gates, it either of the direction switches 36 and 37 is closed, the coil 60 will: be energized, pulling the core 62 downwardly, and closing connection between thecontacts 52 and 67. thus energizing the'coil 68. When the coil 68 is energized the core 71 is pulled down and the cross head 75 will en-Ico gage the contacts 76 and 57, thus energizing the coil 78, upon which the core 83 is pulled downwardly so that the cross head 84 engages the contacts 85 and 55; When the coil 68 is energized the movement of the-core Willithrow out the breaker and kill the board while at the same'time, the coil 78 is energiz'ed. At the same time, the cross head 72 will disengage from the contacts 73 and 74, thus" breaking the gate circuit. When the coil 7 8 is energized the cross head or contact arm 84 will, as mentioned, close the circuit between the contacts 55 and 85. This last closed circuit holds the breaker out until the gates of the car are closed, andwhen the gates ms or" the car are closed, the switch is opened and all of the coils de-energized, and the various contacts released to neutral. Thus it is seen hat when the safety control switch, which 7 closed upon the opening of the gate, isim closed, a circuit to the relay is established,

which throws out the potential switch when the operating line is closed, either by undue closing of either of the switches 36 or 37, or

by an arcing. I When the operating line is closed the automatic brake, of course, will not set, but it is desirable to have these brakes set at all times when the gates are open. Therefore, it is evident that with this invention operating as described, there is provided means for maintaining the operating line open so long as the gates are open.

Having thus described invention what I claim as new and desire to secure by Letters Patent is i In an electrically operated elevatorshav ing electrically controlled gates and brakes and an operating line for supplying electric current to the operating mechanism: direction switches for controlling the flow of current through said operating line; a switch normally closed upon the opening of said gates; and. means operable upon the closing of said second mentioned switch While either of said direction switches is closed for breakin r the circuit to said operating line.

In testimony whereof, I have signed the foregoing.

PHILIP D. TARDIFF.

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