US3396821A - Elevator safety rail and door control - Google Patents

Description

g- 13, 1968 e. w. WEIFORD, JR 3,396,821

ELEVATOR SAFETY RAIL AND DOOR CONTROL Filed June 9, 1967 FIGI h no.4

mvsmon GEORGE w. VIEIFORD Jr.

United States Patent 3,396,821 ELEVATOR SAFETY RAIL AND DOOR CONTROL George W. Weiford, Jr., Medford Lakes, N .J 08055 Filed June 9, 1967, Ser. No. 644,993 3 Claims. (Cl. 187-52) ABSTRACT OF THE DISCLOSURE The combined safety rail and door control for an elevator is designed to be accessible from both outside and within an elevator cab to provide a safety support for elevator passengers departing or entering the cab. The safety rail mounting unit encloses a double acting switching circuit for paralleling an elevator door control circuit and facilitates operation thereof by a rail capable of affording support for a passenger.

The invention relates to a safety rail operable controls to open the door of elevators. Particularly, the invention relates to a conveniently accessible device located on the elevator cab providing support for a passenger and opening or preventing closure of the elevator door.

In automatic elevators and even some operator-controlled elevators, the door or doors of the elevator cab are automatically opened or closed through suitable switches or relays responsive to the actuating controls. In the usual door operating system to which the present invention applies, the door or doors must be fully closed before the elevator cab can move and the door opening control system is such that the door is opened to its full extent and held open for a definite time interval before reclosing. The opening and closing cycle are automatically controlled.

The usual system for automatically closing the door or doors of an elevator includes various safety devices such as photocells actuated by light beams projected across the cab opening and by the so-called safe-edge on the leading edge of the door or doors. These safety devices prevent complete closing of the elevator door or doors and consequent operation of the elevator cab when a person or other object is not completely within the cab or completely outside the elevator cab. In the usual elevator door control system interruption of the light beams or contact with the safe edge causes the door to reopen to its full open position and to remain open for a predetermined interval of time before reclosing.

The usual elevator, particularly the self-operated type elevator, has a panel within the cab which contains the control buttons for selecting floors. This panel also usually contains a button, similar to the floor selecting buttons for opening the elevator door. This door opening button may be manually actuated from within the elevator cab to cause the door or doors to open in the normal manner, i.e., to .open to their full extent and to remain open for a predetermined period of time before reclosing.

These normal and usual door control safety systems have certain inherent limitations which fail to meet frequent desires or needs of elevator users. The safety devices such as the photocells and the safe-edge are inaccessible .or inoperative as soon as elevator door or doors have completely closed and before the cab begins to move. The door-open button, located on the panel with the other control buttons, is accessible from only a limited area Patented Aug. 13, 1968 within the elevator cab, and in a crowded elevator, this button is accessible to only a few passengers. This manual door-open button is not so apparent or distinctive as to be useful or convenient when the desire or need for quick, unexpected use arises.

It is a common experience that just before an elevator door completely closes, some hurrying prospective passenger will call to the occupants of the elevator cab to hold the elevator. Often this is too late to stop the closing of the door by the photocell or safe-edge control and the usual location, size and distinctiveness of the manual door-open control is not such as to lend itself to quick action before the door fully closes and the elevator cab starts to move. Often a passenger who is already in the elevator cab changes his mind at the last moment and wishes to leave the elevator. This decision may be too late to prevent the door from closing by actuating either the photocell or safe-edge controls and often it is impossible for that passenger to find and reach the usual manual door-opening button before the door closes and the cab starts.

Accidents and other problems may occur when the elevator cab is stopped and when passengers are entering or leaving the cab or about to enter or leave the cab. There is necessarily a space or clearance between the bottom of the cab and the floor of the building or other structure in which the elevator is installed and passengers entering .or leaving the elevator cab may trip or stumble at this opening or clearance. This danger is greatly increased if the bottom of the elevator cab is not in exactly the same plane as the floor of the structure or building. For this reason it is highly desirable to provide a support rail or grip within the door frame which can be grasped by a passenger, not only for support, but which will prevent actuation of the door-closing mechanism.

When a person stumbles or trips, or otherwise needs support entering or leaving the elevator cab, it is also important that the elevator door be prevented from closing in the normal automatic fashion or, if the door has started to close, that it be reopened automatically by pressure on the support rail.

Elevators are frequently required for freight as well as passenger service, and often the maximum unobstructed cab opening is required. Any grip or door control mounted within the door frame should be selectively removable when the maximum opening is required for freight. This necessitates not only a unitary door-operating device, but simple releasable interconnection with the electrical circult of the door-actuating system. Preferably, the entire unit should be adaptable to conventional electrical circuits.

The present invention overcomes all of the foregoing difficulties and supplies a need long recognized in the elevator industry. A preferred embodiment of the invention is shown in the drawing and described in the following specification, and it is understood that various modifications can be made Without departing from the invention or the scope of the appended claims.

Referring to the drawing:

FIGURE 1 is a fragmentary sectional view of the door frame or opening of an elevator cab showing the present invention in place.

FIGURE 2 is a front elevation thereof.

FIGURE 3 is a plan view of one form of the present invention with covers removed to show internal structure.

FIGURE 4 is a section taken on line 44 of FIG- URE 3.

FIGURE 5 is a diagrammatic view of one suitable form of control circuit.

One embodiment of the present invention is illustrated in the drawing wherein designates generally the cab of an elevator having an opening or door frame 12 through which passengers enter or leave the cab. This opening is closed by a slidable door (not shown) which may be operated automatically in any known fashion. These slidable doors must close completely before the cab can move, and the door can open only after the cab has come to a complete stop at a floor. Circuits and mechanisms for operating elevator doors are Well known and form no part of the present invention.

The embodiment of the present invention shown in FIGURES 1 to 4 includes a base or bracket 14 firmly secured to the door frame 12 of the elevator cab. A bar 16 is secured to the base or bracket 14 and extends vertically in spaced relation to the bracket into the door opening so that it is readily apparent and may conveniently be grasped by anyone entering or leaving the elevator cab. Thus anyone who trips or stumbles entering or leaving the cab, or who otherwise needs support entering or leaving the cab, may grasp the vertical rod 16.

The vertical rod or bar 16 is mounted for limited rocking or swinging movement on an axis parallel to the bar 16 and such rocking or swinging movement actuates the elevator door causing it to open to its full extent and to remain open so long as the bar 16 is held. When the bar 16 is released, control of the door is returned to the normal door closing mechanism and circuitry.

The bottom end of the vertical rod 16 is secured to the outer end of a horizontal plate or bracket 18, the inner end of which is pivoted at 22 on the top surface of a horizontal lug 24 fixedly secured to the bracket or support 14 by suitable screws or bolts 26. Pins or studs 28 are fixed to the bottom of the plate 18 and project downwardly into enlarged bores 30 in the lug 24. These pins 28 limit the pivotal movement of the bracket 18 carrying the bar 16. Normally, I prefer to limit the movement of the bar to a total of about inch. This permits sufficient movement to actuate the switch controls as hereinafter described but limits the movement so that the bar can and does serve as a firm grip or support for anyone entering or leaving the elevator cab.

The upper end of the bar 16 is secured to a substantially identical upper plate 32 pivotally secured at 34 to a horizontal lug 36 which is in turn fixed to the base 14. One or more vertical pins 38 are fixed to the plate 32 and extend upwardly through over-sized holes or bores 34 in the lug 36 for limiting the pivotal movement of the upper plate 32. Spring means (not shown) urge the plates 18 and 30 to their central position so that the vertical bar, and the bottom and top brackets are normally held in central or neutral position but may be moved a small distance in either direction. As pointed out, the movement of the bar 16 is limited by the pins or studs 28 and 36 engaging the sides of the bores 30 and 38 in the lugs 24 and 34 and upon release, the bar 16 returns to its normal position.

Moving the bar 16 in either direction from its central or neutral position actuates a switch to open the elevator door. One suitable form of switch is shown in FIGURE 3 but it is to be understood that this switching mechanism may take any desired form.

Referring to FIGURES 3 and 4, the upper horizontal plate 30 is pivoted on the upper lug 34 which is secured to the base 14. Switches 40 and 42, such as conventional microswitches, may be secured to the top of the lug 34 by a bolt 43. These switches may be mounted on a separate support or secured directly to the base 14.

A U-shaped actuator 44, fixed to the upper plate or bracket 30 and movable therewith, is provided with two rigid upwardly projecting arms 46 and 48, the arm 46 being in operating alignment with the switch 40 and the arm 48 in operating alignment with the switch 42. When the rod 16 is moved to the right as shown in FIGURE 3, the arm 46 engages and actuates the switch 4 and when the rod 16 is moved to the left as shown in FIGURE 3 the vertical arm 48 engages the switch 42. In normal position the arms are held in spaced relation from their respective switches by the springs (not shown) so that neither switch is actuated. Obviously, a simple double throw switch may be directly connected to the rod 16 or plate 32 to secure the same result. The entire pivot and switch assembly at the upper end of the bar 16 is preferably enclosed in a suitable housing indicated at 50.

Referring to the schematic diagram in FIGURE 5, the block 52 indicates generally the circuit, relay switches, timing devices, etc., for closing the elevator door in normal operation. Safety devices, such as a photocell switch or relay 54 and a safe edge switch or relay 56, are connected in parallel to each other across the actuatswitch or relay 52. A manual door-open switch or relay 58 located on the control panel within the elevator is also connected in parallel to the photocell and safe edge switches 54 and 56. The switches or relays 54, 56, and 58 are normally open, and when any one or more of them is closed, they supersede the normal operating switch or relay 52 and act to open the elevator door.

One of the simplest ways to apply my door actuating unit to the usual existing elevator circuit is by connecting it in parallel with photocell, safe edge and manual door-open switches as shown in FIGURE 5. When the rod 1 6 is moved, switch 40 or 42 is closed and the door opening mechanism actuated in the same way it is actuated by the photocell or safe edge relay 54 or 56.

From the foregoing it will be apparent that I have provided a safety rail within the opening of an elevator cab which not only provides support for passengers entering or leaving the cab, but also prevents premature closing of the elevator door and reopens the door when its closing cycle has begun. The various mechanical and electrical elements are components of my new and useful combination and these individual elements may be changed or modified without changing the combination.

For example, in the embodiment illustrated, the photocell, safe-edge, and manual door opening switches are normally open and are connected in parallel. The normally open switches of the present invention are therefore connected in parallel also. However, it is apparent that the safety switches could be normally closed so that the door would be actuated to open when one of the switches, the photocell, safe-edge, or manual button is actuated. The switches would then be connected in series. In such a case, the switch or relay of the present invention would also be normally closed and would be connected in series with the safety switches or relays. The door-opening sequence would then be actuated upon opening of the switch or relay of the present invention.

I claim:

1. An attachment for an elevator having a cab provided with an opening for the entry and exit of passengers or freight and a door frame surrounding said opening, a door carried by said cab and movable across said door frame for closing said cab and automatic means for opening and closing said door, said attachment comprising an elongated support, means for releasably attaching said support substantially vertically to said door frame, a bar, means for movably mounting said bar on said support in spaced relation thereto for movement substantially parallel to said bar, means carried by said support for limiting the movement of said bar to two extreme positions, resilient means for urging said bar to a position between said extreme positions, switch means secured to said support, switch actuating means operatively secured to :said bar in alignment with said switch means for actuating said switch means when the bar is in either extreme position and means operatively connect- 5 6 ing said switch means to said automatic means for openfor swinging movement on an axis substantially parallel ing the elevator door. to said bar.

2. An attachment for an elevator as defined in claim References Cited 1 in which the elevator is provided with safety switches UNITED STATES PATENTS operatively connected with the automatlc means for open- 5 ing the door and in which the switch means is releasably 2,610,268 9/1952 fiflmlltonoperatively connected in with the safety switches for 2,791,654 5/ 1957 Y- t t v d automat' ans inde endentl of said gf me P y EDWARD A. SROKA, Primary Examiner.

3. An attachment for an elevator as defined in claim 10 H C HORNSBY, Assistant 1 in which the bar is pivotally mounted on said support

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