Suspension device and use thereof in an elevator system, and method
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.
1 . A suspension device for an elevator system for securing a brake and a support means of the elevator system and for measuring a load acting on a car of the elevator system, the suspension device comprising:
a brake adapted to brake the elevator car at a guide rail of the elevator system;
a brake holding assembly holding the brake on the elevator car;
a support means holding assembly holding the support means on the elevator car,
wherein the support means connects the elevator car to a counterweight of the elevator system;
wherein the brake holding assembly is adapted to deform relative to the elevator car in a force direction of a force produced by the brake interacting with the guide rail; and
wherein the support means holding assembly is adapted to deform relative to the elevator car in a force direction produced by the support means.
2 . The suspension device according to claim 1 including a load measuring device measuring an exerted force produced by the deformation of the support means holding assembly and/or of the brake holding assembly, wherein the load measuring device is arranged between the brake holding assembly and the support means holding assembly.
3 . The suspension device according to claim 2 wherein the support means holding assembly and the brake holding assembly are each elastically deformable and are arranged on a web arrangement mounted on the elevator car.
4 . The suspension device according to claim 1 wherein the brake holding assembly and the support means holding assembly are elastically deformable in response a force transmitted during a normal operation of the elevator system.
5 . The suspension device according to claim 1 wherein the brake holding assembly and the support means holding assembly move towards one another or away from one another by less than 2 mm in response a force transmitted during a normal operation of the elevator system.
6 . The suspension device according to claim 1 wherein the brake holding assembly and the support means holding assembly move towards one another or away from one another by less than 1 mm in response a force transmitted during a normal operation of the elevator system.
7 . The suspension device according to claim 1 wherein the support means holding assembly and the brake holding assembly are arranged on a web arrangement mounted on the elevator car, and the brake holding assembly, the support means holding assembly and the web arrangement are formed in one piece as a common part.
8 . The suspension device according to claim 7 wherein the common part is a stamped sheet metal part.
9 . The suspension device according to claim 1 including a load measuring device measuring an exerted force produced by the deformation of the support means holding assembly and/or of the brake holding assembly, and at least one of:
the load measuring device includes a strain gage sensing the exerted force;
the load measuring device includes a force transmission element and is fixed to the brake holding assembly; and
the load measuring device is arranged in the support means holding assembly.
10 . The suspension device according to claim 9 wherein the load measuring device generates an electrical signal representing the exerted force acting on the force transmission element.
11 . The suspension device according to claim 1 wherein the brake is at least one of a holding brake adapted to hold the elevator car during a stop and a safety brake adapted to brake the elevator car in an emergency.
12 . An elevator system comprising:
an elevator car;
a guide rail;
the suspension device according to claim 1 ;
wherein the elevator car is movable along the guide rail;
wherein the suspension device is arranged on the elevator car; and
wherein the brake of the suspension device cooperates with the guide rail to brake the elevator car.
13 . The elevator system according to claim 12 wherein the suspension device is arranged in a lower half of the elevator car.
14 . A method for measuring a load acting on an elevator car, the method comprising the steps of:
activating the brake of the suspension device according to claim 1 , the suspension device being arranged on the elevator car, while the elevator car is stationary; and
measuring a load acting on the elevator car by a load measuring device included in the suspension device.
15 . A method for detecting a slack support means by measuring a load change, the method comprising the steps of:
measuring a change in the load measured according to claim 14 ; and
determining that the load change is greater than a predetermined limit value thereby indicating a slack support means supporting the elevator car.
16 . The method according to claim 15 wherein the load change is measured after stopping the elevator car at a floor and again immediately before departure, wherein the brake is transferred into a catch mode when the load change is greater than the predetermined limit value.