A mechanical elevator safety system with pulley-operated trapdoors

Abstract

A mechanical elevator safety system (100) with pulley-operated trapdoors, comprising: a plurality of trapdoors installed at respective floors within the elevator shaft, each trapdoor configured to cover the opening of the elevator shaft at its respective floor when in the closed position; a pulley system mechanically connected to an elevator car and each of the trapdoors; where the vertical movement of the elevator car activates the pulley system to open the trapdoor on the destination floor before the elevator arrives, and the trapdoor closes automatically as soon as the elevator departs.

Description

[0001] The present invention relates to safety mechanisms for elevators, in particular to a mechanical system having trapdoors operated by a pulley mechanism to prevent accidental falling into the elevator shaft in the event of elevator misalignment or system failure.

[0002] Elevator systems are a ubiquitous component of modern multi-story buildings, providing critical vertical transportation. Ensuring passenger safety has long been a central concern in elevator design. Standard safety mechanisms integrated into most modern elevator systems include door interlocks, infrared motion sensors or light curtains, and emergency stop buttons. These systems collectively aim to prevent accidents and reduce the risks associated with elevator malfunctions.

[0003] Elevator systems play a vital role in modern multi-story buildings, enabling efficient vertical transportation. Passenger safety has always been a top priority in their design, which is why standard safety devices such as door interlocks, motion sensors or light curtains, and emergency stop buttons are widely used. Door interlocks ensure that the doors only open when the elevator car is correctly aligned to a floor, while motion sensors and light curtains detect obstructions near the entrance to prevent the doors from closing prematurely. Emergency stop buttons allow passengers to stop the elevator in critical situations. However, each of these technologies has its limitations. Door interlocks can, in rare cases, fail, causing the doors to open even when the elevator car is not present, posing a serious fall hazard.While motion sensors and light curtains are generally reliable, they can be affected by dust, dirt, or wear over time, reducing their effectiveness. Emergency stop buttons rely on the user's detection and timely response, which may not be the case in panic situations. In addition, fall-restraint systems such as nets or platforms, while used in some industrial settings, are rare in commercial or residential buildings and are designed only to reduce injuries, not prevent falls. Despite advances, a significant safety gap remains: the dangerous and often fatal risk posed when elevator doors open without the car present—a problem that continues to claim lives and underscores the need for improved elevator safety solutions.To solve the problem, the present invention provides a mechanical elevator safety system with belt-driven trapdoors.

[0004] The system is designed to prevent accidental falls into the elevator shaft, especially in situations where the elevator doors open even though the elevator car is not on the respective floor.

[0005] The system includes a fully mechanical trapdoor mechanism that operates without electronic sensors, microcontrollers, or external power sources.

[0006] The system features a pulley-based actuation mechanism that is mechanically synchronized with the vertical movement of the elevator car. This mechanism ensures that the trapdoors installed at each floor landing remain securely closed by default and are only mechanically opened when the elevator car is aligned with the corresponding floor.

[0007] The system is designed to provide enhanced safety with minimal retrofitting, allowing the trapdoor mechanism to be installed in existing elevator shafts without major structural or electrical changes.

[0008] The system is designed as a cost-effective and durable elevator safety solution using simple mechanical components such as pulleys, springs and counterweights.

[0009] The system incorporates fail-safe reset mechanisms, including springs or counterweights, that automatically close the trapdoors in the event of a pulley system failure or mechanical disconnection.

[0010] In one embodiment, the present invention provides a mechanical elevator safety system with pulley-operated trapdoors. The present invention provides a novel and reliable mechanical safety mechanism for elevators aimed at preventing accidental falls into the elevator shaft. The invention comprises a system of trapdoors installed at each floor within the elevator shaft and operated by a mechanically synchronized pulley system directly linked to the movement of the elevator car. In conventional elevator systems, there is a rare but serious risk that the elevator doors will open due to a mechanical or electrical malfunction even when the elevator car is not nearby. This can result in serious injury or death if a person accidentally steps into the open shaft.Existing safety mechanisms rely heavily on sensors and electronic interlocks, which can fail due to power outages, dust, wear, or improper calibration. The disclosed invention overcomes these deficiencies by implementing a purely mechanical trapdoor system that forms a physical barrier above the shaft opening at each floor. The trapdoors are normally in a closed position, covering the floor opening. As the elevator approaches a specific floor, the pulley mechanism mechanically connected to the elevator car is activated, opening the trapdoor just in time for the car to enter the shaft opening. Once the elevator departs, the trapdoors automatically return to the closed position via springs or counterweights, ensuring continuous protection.The system is designed to operate independently of power or sensors, increasing reliability and safety. It can also be integrated into both new and existing elevator systems with minimal structural changes. This makes the invention ideal for a wide range of applications, including residential buildings, commercial complexes, and industrial facilities. By implementing this mechanical trapdoor and pulley system, the invention ensures that the elevator shaft is never exposed when the elevator car is not present, eliminating the risk of falls and increasing overall elevator safety.

[0011] The invention is explained again below with reference to the figure. It shows: Fig. : a schematic block diagram of the pulley-based mechanism for the elevator trapdoor. Fig. : a schematic plan view of a double trapdoor locking mechanism in the elevator shaft Fig. : a side and front view of the elevator hatch operating mechanism.

[0012] Fig. shows a schematic block diagram of the pulley-based elevator trapdoor mechanism (100) according to an embodiment of the present invention. The system includes a mechanical elevator safety mechanism designed to prevent accidental falling into an elevator shaft. A passenger calls the elevator and enters or exits the elevator car. The vertical movement of the elevator car—whether upward or downward—is mechanically connected to a pulley system. As the elevator leaves or approaches a floor, the pulley system transmits the movement to a series of mechanical linkages. These linkages operate the trapdoors located at each floor. As the elevator car approaches a particular floor, the corresponding trapdoor opens downward to allow the elevator car to enter the shaft opening.Once the elevator car leaves the shaft, the trapdoor is returned to its closed position by a counterweight or spring mechanism, ensuring continuous coverage of the shaft and preventing accidental descent. The entire system operates mechanically, eliminating dependence on electronic sensors or power supplies, thus increasing reliability and safety.

[0013] Fig. shows a schematic plan view (101) of a double trapdoor locking mechanism within the elevator shaft according to an embodiment of the present invention. Each trapdoor is equipped with a series of pin holes (shown as open circles) and pins (shown as filled circles) that form a mechanical lock when the trapdoors are in the closed position. This locking configuration improves structural integrity and ensures that the trapdoors function as a uniform surface, preventing misalignment or accidental opening. Located midway between the trapdoors are hoist ropes that are mechanically connected to a pulley system. The vertical movement of the elevator actuates these ropes to open the trapdoors shortly before the elevator arrives and to close them after departure.The locking mechanism not only increases the load-bearing capacity of the trapdoors, but also forms a fail-safe physical barrier above the shaft when there is no elevator car inside.

[0014] Fig.shows the side and front views (102) of the elevator hatch operating mechanism according to an embodiment of the present invention. In the side view (left), an elevator car is shown descending toward floor level, with arrows indicating its downward movement. Below the elevator car are two trapdoors positioned across the shaft opening. These trapdoors are connected by mechanical linkages to a rotatable pulley mounted near the shaft wall. As the elevator descends, the pulley rotates, pulling on the connected ropes and causing the trapdoors to open downward, allowing the elevator car to pass through. In the front view (right), the trapdoors are fully open and rotated downward from their hinge mountings near the wall.This configuration clears the shaft opening for the elevator car while ensuring complete mechanical synchronization. Once the elevator departs, the trapdoors return to the closed position under spring or counterweight force. This illustration illustrates the mechanical coordination between the elevator's movement, the rotating pulley, and the responsive behavior of the trapdoors, which ensure fail-safe coverage of the shaft. List of reference symbols 100 systems

Claims

[1] A mechanical elevator safety system (100) with pulley-operated trapdoors, comprising: a plurality of trapdoors installed at respective floors within the elevator shaft, each trapdoor configured to cover the opening of the elevator shaft at its respective floor when in the closed position; a pulley system mechanically connected to an elevator car and each of the trapdoors; where the vertical movement of the elevator car activates the pulley system to open the trapdoor on the destination floor before the elevator arrives, and the trapdoor closes automatically as soon as the elevator departs. [2] The system (100) of claim 1, wherein the plurality of trapdoors are mounted on a hinge and biased to the closed position by a spring or counterweight mechanism. [3] The system (100) of claim 1, wherein the cable pulley system comprises a vertical main cable extending along the height of the elevator shaft, the main cable being mechanically connected to a series of pulleys at floor level, each corresponding to one of the trapdoors. [4] The system (100) of claim 1, wherein the trapdoors are made of a load-bearing material selected from the group consisting of reinforced steel, an aluminum alloy, and a composite material. [5] The system (100) of claim 1, wherein each floor roller is connected to a corresponding trapdoor via mechanical linkages such that rotation of the roller triggers opening or closing of the trapdoor.

Images