US 5,773,771 A · Apparatus for preventing unintended movement of elevator car

Abstract

Apparatus for restricting motion of an elevator car includes bars or other stiff, elongated members, which are extended outwardly from opposing ends of the elevator car, when the car is positioned in a specified zone of vertical displacement, above the lower edge thereof The displacement zone may be on the order of twelve inches. An elevator control, such as an inspection bank mounted on top of the elevator car, is then operated to move the elevator car slightly downward, to the lower edge of the displacement zone, whereupon the elongated members are brought into solid contact with respective complementary supporting members, joined to opposing elevator guide rails. As the elongated members are extended, a switching arrangement, electrically coupled to the control, is simultaneously actuated to prevent movement of the elevator car above the displacement zone while the elongated members are in their extended mode.

Claims13

Dependent claims

Apparatus for preventing unintended movement of an elevator car wherein an electric circuit is provided for selectively moving the car, and said apparatus comprises:

means for selectively locking said car against downward motion below a selected level;
travel control means for enabling operation of said circuit to controllably move said car to any selected position within a specified zone of displacement extending above said selected level, and for preventing movement of said car beyond said zone;
and
means for actuating said locking means and said travel control means in selected coordinated relationship with each other.

1 more element

Apparatus for preventing unintended movement of an elevator car positioned for vertical movement between first and second guide rails, and provided with an electric control circuit operable to vertically move the car, said apparatus comprising:

first and second elongated members extendible outward from opposing ends of said car to engage corresponding complementary support members, respectively joined to said first and second guide rails;
first and second drive mechanisms attached to said first and second elongated members, respectively, and positioned on opposite sides of said car;
a rotatable member joined to said first and second drive mechanisms and rotatable in a first direction to operate said drive mechanisms to simultaneously extend said first and second elongated members, and rotatable in the opposite direction to operate said drive mechanisms to simultaneously retract said first and second elongated members:
switching means coupled to said control circuit and actuatable to enable said control circuit to move said elevator only within a specified zone of displacement above said level;
and
means for actuating said rotatable member and said switching means together, when said car is in said specified zone.

3 more elements

Dependencies are inferred from the claim text.

Apparatus for preventing unintended movement of elevator car

Life of this patent

Apparatus for preventing unintended movement of elevator car

Life of this patent

Abstract

Claims13