An elevator system (20) load bearing assembly (30) includes a plurality of load bearing members (32-38). At least one of the load bearing members (32-38) has a load carrying capacity that is different than at least one other of the load bearing members (32-38). A disclosed example includes equal numbers of load bearing members (32, 38) having a first load carrying capacity and equal numbers of load bearing members (34, 36) having a second, different load carrying capacities. Another example includes at least three different load carrying capacities. With the disclosed examples, the aggregate load carrying capacity of an elevator load bearing assembly (30) can more closely meet the load carrying requirements for a given elevator system without over-roping the system.

An elevator system (20) load bearing assembly (30) includes a plurality of load bearing members (32-38). At least one of the load bearing members (32-38) has a load carrying capacity that is different than at least one other of the load bearing members (32-38). A disclosed example includes equal numbers of load bearing members (32, 38) having a first load carrying capacity and equal numbers of load bearing members (34, 36) having a second, different load carrying capacities. Another example includes at least three different load carrying capacities. With the disclosed examples, the aggregate load carrying capacity of an elevator load bearing assembly (30) can more closely meet the load carrying requirements for a given elevator system without over-roping the system.

The object of the invention is a tensioning arrangement for a traction means of an elevator, which arrangement comprises at least an elevator car configured to move up and down in an elevator hoistway and at least one or more compensating weights, which are for their part connected to support the elevator car by the aid of their own support means, such as by the aid of ropes or belts and also of diverting pulleys, and a hoisting machine provided with at least one traction sheave or corresponding, and also at least one traction means (7) such as a belt, rope or chain, which is configured to transmit the rotational movement of the traction sheave into movement of the elevator car and of the compensating weights. The traction means (7) is fixed from at least one of its ends to a fixing means (1) providing an essentially constant tensioning force.

The object of the invention is a tensioning arrangement for a traction means of an elevator, which arrangement comprises at least an elevator car configured to move up and down in an elevator hoistway and at least one or more compensating weights, which are for their part connected to support the elevator car by the aid of their own support means, such as by the aid of ropes or belts and also of diverting pulleys, and a hoisting machine provided with at least one traction sheave or corresponding, and also at least one traction means (7) such as a belt, rope or chain, which is configured to transmit the rotational movement of the traction sheave into movement of the elevator car and of the compensating weights. The traction means (7) is fixed from at least one of its ends to a fixing means (1) providing an essentially constant tensioning force.

A counterweight slack detection switch including a body, a first belt guide mounted to the body and configured to engage a first side of a tension member, a second belt guide mounted to the body and configured to engage the first side of the tension member, a lever arm having a first end and a second end, the first end pivotally mounted to the body, a deflectable member biasing the lever arm relative to the body, a third belt guide mounted to the second end of the lever arm and configured to bias the tension member from a tension position to a slack position, and a switch mounted to the body and configured to contact the tension member when the tension member is in at least one of the tension position and the slack position.

A counterweight slack detection switch including a body, a first belt guide mounted to the body and configured to engage a first side of a tension member, a second belt guide mounted to the body and configured to engage the first side of the tension member, a lever arm having a first end and a second end, the first end pivotally mounted to the body, a deflectable member biasing the lever arm relative to the body, a third belt guide mounted to the second end of the lever arm and configured to bias the tension member from a tension position to a slack position, and a switch mounted to the body and configured to contact the tension member when the tension member is in at least one of the tension position and the slack position.

A method for roping an elevator. At the bottom part of the elevator shaft the hoisting ropes are routed under the pulleys of the elevator car. Then the elevator car and the counterweight are hoisted to the upper part of the shaft where the first ends of the hoisting ropes are routed through the traction sheave and the counterweight pulleys. After that the first rope ends are fixed to the counterweight side rope terminals and the counterweight is lowered to the bottom part of the shaft. During the descent the hoisting ropes are unwound from the reels through the whole roping system with the help of the mass of the counterweight. Finally, the second ends of the hoisting ropes are fixed to the car side rope terminal and tightened to the correct tension.

A method for roping an elevator. At the bottom part of the elevator shaft the hoisting ropes are routed under the pulleys of the elevator car. Then the elevator car and the counterweight are hoisted to the upper part of the shaft where the first ends of the hoisting ropes are routed through the traction sheave and the counterweight pulleys. After that the first rope ends are fixed to the counterweight side rope terminals and the counterweight is lowered to the bottom part of the shaft. During the descent the hoisting ropes are unwound from the reels through the whole roping system with the help of the mass of the counterweight. Finally, the second ends of the hoisting ropes are fixed to the car side rope terminal and tightened to the correct tension.

The invention relates to a drive machinery for an elevator, the drive machinery comprising a rotatable drive sheave for driving plurality of ropes of the elevator, and a motor for rotating the drive sheave; the drive sheave comprising a drive sheave body rotatable around a rotational axis; and plurality of rim arrangements mounted on the drive sheave body side by side in direction of said rotational axis, each said rim arrangement defining a circular outer rim for transmitting traction to a rope, said circular outer rims being coaxial with each other. The diameter of the circular outer rim of one or more of said rim arrangements is individually adjustable for enlarging or reducing the turning radius of a rope passing around the circular outer rim in question. The invention also relates to an elevator comprising said drive machinery.

The invention relates to a drive machinery for an elevator, the drive machinery comprising a rotatable drive sheave for driving plurality of ropes of the elevator, and a motor for rotating the drive sheave; the drive sheave comprising a drive sheave body rotatable around a rotational axis; and plurality of rim arrangements mounted on the drive sheave body side by side in direction of said rotational axis, each said rim arrangement defining a circular outer rim for transmitting traction to a rope, said circular outer rims being coaxial with each other. The diameter of the circular outer rim of one or more of said rim arrangements is individually adjustable for enlarging or reducing the turning radius of a rope passing around the circular outer rim in question. The invention also relates to an elevator comprising said drive machinery.