Method and system for increasing the availability of an elevator standing unused at a landing

Abstract

In the method for increasing the availability of an elevator standing unused at a landing the ambient temperature of at least one electrical device of the elevator is measured; and when the ambient temperature falls below a threshold value, electric current is conducted to at least one electrical device of the elevator for warming the electrical device in question. The patent application also includes an independent claim for a system for increasing the availability of an elevator standing unused at a landing.

Claims

1. A method for controlling an ambient temperature of at least one electrical device of an elevator standing unused at a landing, the method comprising: measuring the ambient temperature of the at least one electrical device of the elevator, the at least one electrical device being one or more of (i) a frequency converter or control card included in a hoisting machine of the elevator, (ii) an elevator control unit, (iii) a call-giving device, (iv) an electricity supply device for holding brakes, and (v) a control device of an automatic door of the elevator; and controlling the ambient temperature by supplying power to the at least one electrical device in response to the ambient temperature being below a threshold value.

2. The method according to claim 1, wherein the controlling comprises: supplying the power at a level sufficient to drive the elevator without passengers during a warm-up run of the elevator.

3. The method according to claim 1, wherein the controlling comprises: supplying the power to the at least one electrical device while the elevator remains stationary.

4. The method according to claim 1, wherein the at least one electrical device is the frequency converter or control card included in the hoisting machine, and excitation current that does not form rotating torque is used for warming windings of an electric motor of the hoisting machine.

5. The method according to claim 1, wherein the at least one electrical device is a brake resistor in an intermediate circuit of the frequency converter of the hoisting machine, the brake resistor being configured to consume regenerative braking energy of an elevator motor of the hoisting machine as heat.

6. An elevator comprising: at least one electrical device, the at least one electrical device being one or more of (i) a frequency converter or control card included in a hoisting machine of the elevator, (ii) an elevator control unit, (iii) a call-giving device, (iv) an electricity supply device for holding brakes, and (v) a control device of an automatic door of the elevator; at least one sensor configured to measure an ambient temperature of the at least one electrical device; and a controller configured to control the ambient temperature by supplying power to the at least one electrical device in response to the ambient temperature being below a threshold value.

7. The elevator according to claim 6, wherein the controller is configured to supply the power at a level sufficient to drive the elevator without passengers during a warm-up run of the elevator.

8. The elevator according to claim 6, wherein the controller is configured to supply the power to the at least one electrical device while the elevator remains stationary.

9. The elevator according to claim 6, wherein the at least one electrical device is the frequency converter or control card included in the hoisting machine, and excitation current that does not form rotating torque is used for warming windings of an electric motor of the hoisting machine.

10. The elevator according to claim 6, wherein the at least one electrical device is a brake resistor in an intermediate circuit of the frequency converter of the hoisting machine, the brake resistor being configured to consume regenerative braking energy of an elevator motor of the hoisting machine as heat.

11. The method according to claim 1, wherein the measuring includes measuring the ambient temperature using at least one sensor such that a same one of the at least one sensor is also configured to instruct a controller to prevent running of the elevator in response to the ambient temperature being below a second threshold.

12. The elevator according to claim 6, wherein a same one of the at least one sensor is also configured to instruct the controller to prevent running of the elevator in response to the ambient temperature being below a second threshold.

13. The method according to claim 1, wherein the controlling comprises: supplying the power directly to the at least one electrical device to operate same.

14. The elevator according to claim 6, wherein the controller is configured to supply the power directly to the at least one electrical device to operate same.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) At least some example embodiments will become more fully understood from the detailed description provided below and the accompanying drawings, wherein like elements are represented by like reference numerals, which are given by way of illustration only and thus are not limiting of example embodiments and wherein:

(2) FIG. 1 is a block diagram of an elevator according to some example embodiments; and

(3) FIG. 2 is a method of controlling an ambient temperature of at least one electrical device of an elevator according to some example embodiments.

DETAILED DESCRIPTION

(4) FIG. 1 is a block diagram of an elevator according to some example embodiments. FIG. 2 is a method of controlling an ambient temperature of at least one electrical device of an elevator according to some example embodiments.

(5) Referring to FIGS. 1 and 2, an elevator 100 may include at least one electrical device 110, at least one sensor 120, and a controller 130.

(6) In some example embodiments, in operation S210, the controller 130 may measure an ambient temperature of the at least one electrical device 110 based on data from the at least one sensor 120. In operation S220, the controller 130 may control the ambient temperature based a result of the measuring.

(7) According to the invention the ambient temperature of the electrical devices of an elevator is measured and electric power is supplied to at least one electrical device according to need in such a way that the ambient temperature is not able to drop too low such that the aforementioned problems would start to appear.

(8) This measurement must be implemented specifically during the standstill times of the elevator, i.e. during those times when there is no elevator travel and when the drive devices are able to cool owing to the standing of the elevator.

(9) The method can be implemented with different embodiments.

(10) We have designed at least the following two embodiments of the method: A special warm-up run is, if necessary, driven with the elevator, in which case current must be supplied to the electrical devices needed for the warm-up run. In this case the electrical devices warm up. Power is supplied to the elevator electrical devices of the elevator without driving with the elevator. The electrical devices to be supplied at any given time are selected on the basis of the measuring data received from sensors measuring the ambient temperature. This embodiment is preferred e.g. in situations when a run with the elevator is forbidden during a standstill of the elevator. In some elevator systems elevator travel is restricted e.g. at nighttime.

(11) The aforementioned electrical devices can be e.g. an electric drive of an elevator, or more precisely a hoisting machine, or an electricity supply device (frequency converter) or control card (low-voltage card) of the hoisting machine, comprised in the electric drive. In this case heat can be effectively generated e.g. with the hoisting machine by supplying so-called excitation current, which does not form rotating torque but, however, generates heat in the windings of the electric motor of the hoisting machine. On the other hand, heat can also be effectively generated with a brake resistor possibly in the intermediate circuit of a frequency converter, which brake resistor consumes the regenerative braking energy of the elevator motor as heat.

(12) The electrical device can be an elevator control unit, which controls the travel of the elevators in the elevator hoistway according to a speed reference.

(13) The electrical device can be a call-giving device, with which an elevator call is given.

(14) The electrical device can be an electricity supply device of, or control device of, the holding brakes of the hoisting machine of the elevator

(15) The electrical device can be a control device of an automatic door of the elevator.

(16) More particularly problems might occur with electrical devices that are disposed in the elevator hoistway, such as fixed to a wall part of the elevator hoistway or disposed in the pit of the elevator hoistway.

(17) A thermal resistor can be disposed in some electrical cubicle (cubicle), to which resistor current is supplied only for raising the ambient temperature of the electrical devices of the elevator.

(18) The invention must not be regarded as being limited only to the claims below but instead should be understood to include all legal equivalents of said claims and combinations of the embodiments presented.