Elevator lift cage load measuring assembly
Load measuring equipment has a small-area load sensor arranged between a support and a first damping body for vibration damping of parts relative to the support. The support may be a bracket and the parts may be a lift drive engine. The force on the sensor, which may be the force emanating from an engine foot of the drive engine made up of cage weight, cage load, weight of the counterweight, weight of the support cables and weight of the drive unit, is a small portion of the force on the support, such as the bracket. The ratio of the area of the first damping body to the load sensor determines the ratio of the force acting on the damping body to the force acting on L, and sensed by Z the load sensor.
1. An assembly for determining a load in a lift cage of a lift, comprising a damping body bearer located on a first part acted on by vibration, a vibration damping body located on a second part acted on by vibration and to be vibration damped with respect to the first part, the bearer and damping body having a construction wherein each has an adjacent surface with a corresponding effective area intended to be in contact with the other while under the load, and a load sensor positioned between the adjacent surfaces and in the effective area of the damping body and having a thickness such that it may be inserted between the adjacent surfaces without substantial change of the construction from a configuration in which the load sensor is not present.
2. The assembly according to claim 1 , wherein the load sensor has a small measurement region area in comparison with the effective area of the damping body and is thereby exposed to only a fraction of a force exerted on the damping body by the parts acted on by vibration.
3. The assembly according to claim 2 , wherein the sensor's thickness is no greater than approximately 1 mm.
4. The assembly according to claim 2 or 3 , wherein an area ratio of the load sensor measurement region to the effective area of the damping body is no greater than approximately 1:10.
5. A lift with a lift cage comprising the assembly of claim 1 or 2 .
6. A method for installation of a load sensor of a size and construction such that it may be mounted in contact between a bearer and a damping body without substantial constructional change of the bearer or the damping body in a support for parts that are acted on by vibration and that are supported upon the damping body carried by the bearer for vibration damping of the parts relative to the bearer, comprising the steps of:
raising the parts from the bearer until a small gap can be established between the bearer and the damping body;
inserting the load sensor into the gap without a constructional change to the bearer or the damping body; and
lowering the parts onto the bearer.
7. The method according to claim 6 , wherein the part and bearer comprise portions of a lift cage of a lift retrofitted with the load sensor.