An elevator installation and a method of operating the elevator system for temporary transportation of an overload within the elevator installation includes a car and a counterweight interconnected by one or more suspension ropes engaging a traction sheave that is driven by a motor. The traction between the suspension ropes and the traction sheave is enhanced independently of the counterweight for intended overload operation.

An elevator car load measurement system for determining a load of an elevator car includes a plurality of at least two force sensors that are daisy-chained and connected to a controller for determining the load. Each force sensor measures a force exerted by the elevator car on the respective force sensor and generates a frequency signal with a square-wave form, wherein the frequency signal is proportional to the respective measured force. At least one of the force sensors adds a first frequency signal received from the previous force sensor along the daisy chain a second frequency signal generated by the at least one force sensor to generate a frequency sum signal, the last of the force sensors in the daisy chain forwards the frequency sum signal to the controller.

An elevator load weighing system (100) includes a brake assembly (104) configured to apply a braking force that inhibits vertical movement of an elevator car (106), and rotate in response to realizing a torque applied thereto. A position monitoring mechanism (112) is coupled to the brake assembly (104) and is configured to output a position signal in response to a rotation of the brake assembly (104). An electronic elevator control module (102) is configured to determine a zero-torque position of the brake assembly (104) prior to engaging the brake assembly (104). The electronic elevator control module (102) is further configured to detect at least one rotational brake displacement of the brake assembly (104) based on the position signal.

A system includes an elevator system including an elevator car. The system also includes a control system configured to receive a crowd reduction indicator, determine an elevator car load reduction for the elevator car based on the crowd reduction indicator, adjust an elevator car load limit based on the elevator car load reduction, and trigger a mitigation action in the elevator system based on detecting a condition that exceeds the elevator car load limit.

The invention concerns a method, system and computer program for monitoring the run of a roping interconnecting a car and a counterweight of an elevator and for detecting an abnormal operation condition during the drive of a traction sheave intending therewith the car and the counterweight to be moved via said roping. Said roping is running on its way from the car to the traction sheave via at least one pulley and on its way from the counterweight to the traction sheave via at least one pulley, wherein the rotation of said at least two pulleys is monitored by sensing their rotation. These rotation data are then analysed in view of a mutual correlation indicating therewith a synchronized run of the roping on either side of the traction sheave, and detecting therewith an abnormal situation when detecting an absence of such correlation.

A suspension member load sensor configured for use with a suspension member in an elevator system is provided. The suspension member load sensor includes a housing bounded by an upper cover plate and a lower cover plate. The upper cover plate and the lower cover plates are configured to receive a rod extending therethrough. The lower cover plate is configured to seat adjacent a mounting plate. A strain gauge is disposed within the housing and configured to produce an electrical signal commensurate with a load on the suspension member. A plurality of spaced apart projections extend outwardly from a lower surface of the lower cover plate. The projections are configured to define a location for the introduction of force into the load sensor.

An elevator installation and a method of operating the elevator system for temporary transportation of an overload within the elevator installation includes a car and a counterweight interconnected by one or more suspension ropes engaging a traction sheave that is driven by a motor. The traction between the suspension ropes and the traction sheave is enhanced independently of the counterweight for intended overload operation.

An elevator car load measurement system for determining a load of an elevator car includes a plurality of at least two force sensors that are daisy-chained and connected to a controller for determining the load. Each force sensor measures a force exerted by the elevator car on the respective force sensor and generates a frequency signal with a square-wave form, wherein the frequency signal is proportional to the respective measured force. At least one of the force sensors adds a first frequency signal received from the previous force sensor along the daisy chain a second frequency signal generated by the at least one force sensor to generate a frequency sum signal, the last of the force sensors in the daisy chain forwards the frequency sum signal to the controller.

A suspension member load sensor configured for use with a suspension member in an elevator system is provided. The suspension member load sensor includes a housing bounded by an upper cover plate and a lower cover plate. The upper cover plate and the lower cover plates are configured to receive a rod extending therethrough. The lower cover plate is configured to seat adjacent a mounting plate. A strain gauge is disposed within the housing and configured to produce an electrical signal commensurate with a load on the suspension member. A plurality of spaced apart projections extend outwardly from a lower surface of the lower cover plate. The projections are configured to define a location for the introduction of force into the load sensor.

A suspension device has at least one brake for braking an elevator car relative to a stationary component of an elevator system, a brake holding assembly holding the brake on the elevator car, and a support means holding assembly holding a support means on the elevator car. The support means connects the elevator car to a counterweight of the elevator system. The brake holding assembly holds the brake against the elevator car such that the brake moves relative to the elevator car in a force direction produced by the brake. The support means holding assembly holds the support means against the elevator car such that the support means moves relative to the elevator car substantially in a force direction produced by the support means. A load measuring device measures an exerted force produced by relative movement of the support means and/or the brake.