US508680A

US508680A - Electric elevator

Info

Publication number: US508680A
Authority: US
Publication date: 1893-11-14
Anticipated expiration: 1910-11-14

Description

(No Model.)

r A. T. CHASE.

ELECTRIC ELEVATOR.

No. 508,680. Patented Nov. 1-4, 1893..

F'|E I WITNESSES A INVENTDR 088 8% W 5 UNrrnn TATES Fries.

PATENT ARTHUR TAFT CHASE, OF CAMBRIDGE, MASSACHUSETTS, ASSIGNUR TO THE THOMSON-HOUSTON ELECTRIC COMPANY, OF CONNECTICUT ELECTRIC ELEVATOR.

SPECIFICATION forming part of Letters Patent No. 508,689, dated November 14, 1893. Applicationfiledbecember16,1891, Serialllo. 415,223. (Nomodel-l To whom it may concern:

Be it known that I, ARTHUR TAFT CHASE, a citizen of the United States, residing at Cambridge, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Electric Elevators, of which the following is a specification. This invention relates to improvements in circuit controlling devices for electric ele- ID vators, the object of the invention being to break the circuit through the field magnet, at times when the elevator is not at work for a considerable period, so as to economize the current used.

As is well known there are times, frequently of considerable duration, during which an elevator is not at work, the elevator cal) being at such times, usually at the bottom of the hatchway. In the case of electric ele- 2o vators when the current is kept turned on through the field magnet during such times, a considerable waste of electric energy occurs. To obviate this waste, I take advantage of the above mentioned fact that when the elevator is not running the cab is usually at the bottom of the shaft, with its door and the door into the hatchway at that point open. On one of these doors, for example, the hatchway door, I place a projection or sL-iker, 0 which when the door is opened engages with a switch connected to the field magnet circuit of the elevator operating motor, so as to cause such circuit to be opened and cut off the current from the field magnet; When 5 the door is closed a reverse motion of the switch is effected, again energizing the field magnet and putting. the motor in operative condition.

In the accompanying drawings, Figure 1 is an elevation of a portion of the lower part of the hatchway, showing the door, the striker thereon and the switch operated thereby.

Fig. 2 is a vertical section on the line 2-2 in Fig. 1, also showing a portion of the cab. Fig.

3is an enlarged view of the switch in the open position. Fig. 4 is a diagram of the circuit connections.

A represents a part of the elevator shaft,

13 the cab and C an elevator door onthe lower or ground floor. An arm or projection D attached to this door extends upwardly and carries an anti-friction roller 01, which, when thedoor is moved in one direction or the other, engages with the forked end 6 of an arm of a double-pole switch E, which is placed in or near the hatchway, and controlsthe circuit of the field magnet of the elevator operating motor.

As shown in Fig. 3 the switch may consist .of two metal arms 6, e pivoted at land 2 re- 6o spectively, connected by an insulating link e so as to have a parallel motion, and. engaging with contacts 3, 4:. The line connections 1,1 from the constant potential circuit are brought to pivots 1 and 2, and the field magnet or motor connections fif, lead from contacts 3, 4. When the elevator door is closed, as shown in Fig. 1, the switch levers e, e engage with the contacts 3, 4, closing the field magnet or motor circuit, and the roller 01 7o stands somewhat to the right of the fork e formed on the end of the switch lever 6 Now when the door is opened by sliding it to the left, the roller 01 strikes an arm of the fork e and throws the switch to the position of Fig. 3, and then passes on to the end of its travel. When the door is again closed, the roller returning, strikesthe other end or arm of the fork, and carries the switch back. In order to insure this operation, to provide a quick break, and to hold the fork in its extreme position on either side so as to engage properly with the roller, 1 provide'a doublethrow spring 5 which may be attached at one end'to a fixed support and at the other end to 8 5 the lever 6 so as totend to hold the switch levers at either of their extreme positions, and to quickly bring them to such positions as soon as they have once passed the central position. go

As before stated this invention is especially adapted for use with a constant potential circuit, the leads L, L of which are indicated in Fig. l, connections Z, Z being taken through the switch E and connections f to the field magnet F.

In derivation with the field magnet circuit is the armature circuit a, a including the armature A of the elevator operating motor, and a controlling rheostat and circuit breaker 10o R having resistances r a series of contacts 7' therefor, line terminals Z Z and a controlling switch lever 25, which co-operating with the line and resistance contacts, serve to make, break, reverse and vary the resistance of the armature circuit. Any other approved form of controller for the armature circuit of the motor may however, be adopted in place of that here shown.

My invention relates more particularly to the combination with an armature circuit having a controlling means therein, of a derived field magnet circuit having connections to the line independent of the circuit controller in the armature circuit, but controlled by an independent switch which may be left closed during such ordinary reversals and stoppages as occur while the elevator is running up or down the shaft, and may be opened at times when the elevator is stopped for such a period as to make it desirable to save the waste of current through the field magnet. The circuit breaker controlling the field magnet connections may obviously be operated in other ways so as to obtain the above result. For example, the striker D may be attached to either the hatchway door, as shown, or to the cab door, or to any other movable part within reach of the elevator attendant when the cab is in a position at which a long stop is likely to be made.

It is desirable to make the circuit breaking switch e, 8 open the connections of both the field magnet and the armature circuits, so as to prevent the possibility of the current being turned onto the armature while the field magnet is inactive. I therefore prefer to derive the armature and field circuits from common connections controlled by this switch as shown atfif, in Fig. 4.

What I claim as new, and desire to secure by Letters Patent, is-

1. In an electric elevator, the combination with the cab carrying a controlling device for the armature circuit, of a double pole switch controlling the line connections to the field magnet and armature and located near the ole vator shaft, and a door giving access to said shaft and having an arm to positively open said switch when the door is opened, and vice versa, substantially as described.

2. In an electric elevator, the combination with the cab B, of the armature controlling device mounted in the cab, the shunt wound motor, the spring actuated double pole switch controlling the connections from the mains to the motor and having a fork c, and the elevator shaft door 0, carrying an arm I) adapted to strike and operate the forke both in the opening and closing of the door, substantially as described.

In witness whereof I have hereunto set my hand this 11th day of December, 1891.

ARTHUR TAFT CHASE.

Witnesses:

A. P. KNIGHT, O. L. HAYNES.