Drive engine arrangement with sensor-monitored fan for an elevator system

Abstract

A drive engine arrangement for an elevator system includes a drive engine for driving suspension traction media for displacing an elevator car, a fan for generating a fluid flow for cooling the drive engine and a fluid flow sensor. The fluid flow sensor senses the fluid flow generated by the fan. Accordingly, using the fluid flow sensor, it can be determined whether or not the fan is currently operating. By e.g. comparing the fan's behavior with previous operation patterns and/or by additionally measuring a temperature of the drive engine with a temperature sensor, it can be monitored whether the fan is operating correctly or whether e.g. cooling requirements may be compromised due to a malfunction of the fan. Such monitoring can be performed remotely and/or automatically.

Claims

1. A drive engine arrangement for an elevator system comprising: a drive engine for driving suspension traction means for displacing an elevator car; a fan generating a fluid flow cooling the drive engine; and a fluid flow sensor sensing the fluid flow generated by the fan and generating an indication of an operating condition of the fan based upon the sensed fluid flow.

2. The drive engine arrangement according to claim 1 wherein the fluid flow sensor includes a deflectable flap arranged in a path of the fluid flow generated by the fan.

3. The drive engine arrangement according to claim 2 wherein the fluid flow sensor includes a switch activated by deflection of the deflectable flap.

4. The drive engine arrangement according to claim 1 wherein the drive engine includes a housing and the fluid flow sensor is attached to the housing.

5. The drive engine arrangement according to claim 4 wherein the fluid flow sensor is attached to an outside surface of the housing.

6. The drive engine arrangement according to claim 1 wherein an electrical circuitry of the fluid flow sensor is separated from an electrical circuitry of the drive engine.

7. The drive engine arrangement according to claim 1 including a temperature sensor measuring a temperature in the drive engine.

8. An elevator system comprising: a drive engine arrangement including a drive engine for driving suspension traction means for displacing an elevator car of the elevator system, a fan generating a fluid flow cooling the drive engine, and a fluid flow sensor sensing the fluid flow generated by the fan and generating a signal representing an operating condition of the fan based upon the sensed fluid flow; and a controller for determining an operation status of the fan based upon the signal received from the fluid flow sensor.

9. The elevator system according to claim 8 wherein the controller is arranged at a remote position from the drive engine.

10. The elevator system according to claim 8 wherein the controller determines the operation status of the fan based on a comparison of a current one of the signal from the fluid flow sensor with at least one of a reference signal value, multiple reference signal values, a time pattern of reference signals and a reference signal range.

11. The elevator system according to claim 8 wherein the controller determines the operation status of the fan taking into account a signal received from a temperature sensor at the drive engine arrangement.

12. The elevator system according to claim 8 wherein the controller determines the operation status of the fan taking into account signals received from an elevator control of the elevator system.

13. A method of operating an elevator system according to claim 8, the method comprising the steps of: operating the fan to generate the fluid flow; operating the controller to determine an operation status of the fan based on the signal received from the fluid flow sensor of the drive engine arrangement; and initiating a countermeasure when the controller determines that the operation status is a critical operation status.

14. The method according to claim 13 including prior to the step of determining retrofitting the fluid flow sensor to the drive engine of the elevator system.

15. An elevator system comprising: a drive engine arrangement including a drive engine for driving suspension traction means for displacing an elevator car of the elevator system, a fan for generating a fluid flow for cooling the drive engine, and a fluid flow sensor sensing the fluid flow generated by the fan and generating a signal representing an operating condition of the fan based upon the sensed fluid flow; a controller for determining an operation status of the fan based upon the signal received from the fluid flow sensor; wherein the controller determines the operation status of the fan based on a comparison of a current one of the signal from the fluid flow sensor with at least one of a reference signal value, multiple reference signal values, a time pattern of reference signals and a reference signal range; and wherein the controller determines at least one of the reference signal value, the multiple reference signal values, the time pattern of reference signals and the reference signal range during a learning procedure by operating the drive engine in a predetermined operation state and acquiring the signal from the fluid flow sensor during such operation.

Description

DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows an elevator system comprising a drive engine arrangement according to an embodiment of the present invention.

(2) FIG. 2 show a cross sectional side view through a drive engine according to an embodiment of the present invention.

(3) The figures are only schematic and not to scale. Same reference signs refer to same or similar features throughout the figures.

DETAILED DESCRIPTION

(4) FIG. 1 shows an elevator system 100 comprising a drive engine arrangement 1 according to an embodiment of the present invention. The drive engine arrangement 1 comprises a drive engine 3 in which an electric motor (not explicitly shown in FIG. 1) drives a traction sheave 11 into rotating motion. The traction sheave 11 drives a suspension traction means 5 such as one or more belts or ropes. The suspension traction means 5 suspends an elevator car 7 as well as a counterweight 17. An operation of the drive engine 3 is controlled by an elevator control 15 in communication with a controller 102 via a signal transmission line 21.

(5) The drive engine arrangement 1 furthermore comprises a fluid flow sensor 9. The fluid flow sensor 9 is directly and mechanically coupled to the drive engine 3. Preferably, the fluid flow sensor 9 is attached to an outside surface of a housing 13 enclosing the drive engine's 3 components such as its electric motor. Signals from the fluid flow sensor 9 are transmitted to a controller 102 via a signal transmission line 19, such controller 102 being positioned remotely from the drive engine 3.

(6) While the visualization of FIG. 1 shows the fluid flow sensor 9 to be disposed at a side of the drive engine's 3 housing 13, this is mainly for ease of visualization. In principle, the fluid flow sensor 9 may be disposed at any suitable location at the drive engine 3 as long as it is in the fluid flow generated by the drive engine's fan (not shown in FIG. 1). However, in most implementations, the drive engine's fan is disposed at a rear side of the drive engine 3, i.e. a side opposite to the side at which the traction sheave 11 is disposed, such as to generate a fluid flow through the drive engine 3 in parallel to the drive engine's longitudinal axis. Accordingly, it may be preferable to attach the fluid flow sensor 9 to a surface of the housing 13 at the rear side of the drive engine 3.

(7) FIG. 2 shows a cross-sectional view through a drive engine arrangement 1 in according to such embodiment. The drive engine 3 comprises a main electric motor 23 and a power supply control 29. The main electric motor 23 is mechanically connected to the sheave 11 for driving the suspension traction means 5. The drive engine 3 furthermore comprises the fan 25. The fan 25 comprises a small electric motor 27 and fan blades 26 driven by the motor 27 into rotating motion upon operating the fan 25. All these components, i.e. the main electric motor 23, the power supply control 29 and the fan 25, are comprised in and enclosed by the housing 13. At a rear side 14, the housing 13 comprises several openings and slots 41. Through these openings and slots 41, a fluid such as air from an environment may enter into the housing 13. Accordingly, upon operating the fan 25, a fluid flow 35 may be drawn into the housing 13 and flow along components comprised in the housing in order to absorb heat, i.e. in order to actively cool these components. The fluid flow 35 may then leave the housing 13 through other openings or slots (not shown).

(8) The fluid flow sensor 9 is attached to the surface at the rear side 14 of the housing 13 in a region adjacent to one of the openings or slots 41. The sensor 9 comprises a housing 43 having openings or slots at an entrance side 45 as well as at an opposite exit side abutting to the housing 13 of the drive engine 3. Accordingly, when the fan 25 is operated, a portion 37 of the fluid flow 35 generated by the fan 25 is drawn through the fluid flow sensor 9.

(9) Inside the housing 43, the fluid flow sensor 9 comprises the deflectable flap 31. This deflectable flap 31 is hinged at one end while being deflectable with the other end. Furthermore, the fluid flow sensor 9 comprises a switch 33 which may be activated and deactivated, respectively, upon the deflectable flap 31 being moved from an open state to the closed state, or vice versa. Accordingly, the deflectable flap 31, in its closed state, may come into mechanical contact with the switch 33 or at least may come close to the switch 33 such as to activate/deactivate it, whereas in its open state, the flap 31 is positioned away from the switch 33 such as to deactivate/activate it. Without external forces being applied to the flap 31, the flap 31 is biased towards its closed state in which it significantly hinders a fluid flow 37 through the fluid flow sensor 9.

(10) Accordingly, when the fan 25 is operated and draws the portion 37 of the fluid flow 35 through the fluid flow sensor 9, the flap 31 is deflected from its closed state into its open state. Such deflection of the flap 31 occurring upon correct operation of the fan 25 may then be remotely detected from a signal generated by the switch 33.

(11) For monitoring correct operability of the fan 25, it may have been determined during a preceding learning procedure how the fan 25 typically behaves during correct operation, i.e. as long as no defect or failure occurs. For example, the learning procedure may be performed after installing the elevator system. Therein, the drive engine 3 may be operated in accordance with specified operation characteristics and it may be observed how the fan 25 is activated and deactivated during such specified operation. Typically, the fan's 25 operation depends on the current temperature of the main motor 23, the supply control 29 and/or other components comprised in the drive engine 3, wherein the temperature of these components generally depends on a duration and/or power requirements with which these components are operated. Accordingly, typical time-dependent patterns of activating and deactivating the fan 25 may occur. Such patterns may then be used as time patterns of reference signals. During subsequent normal operation of the elevator system, any currently occurring activation and deactivation of the fan 25 detected using the fluid flow sensor 9 may then for example be compared to such previously acquired time patterns of reference signals.

(12) Alternatively or additionally, the fluid flow sensor 9 may comprise the temperature sensor 39 with which a temperature of the drive engine 3 may be measured. For example, such temperature sensor 39 may directly abut to the housing 13 of the drive engine 3. In a preceding learning procedure or, alternatively, through other experiments, simulations or calculations, it may be determined at which temperature measured by the temperature sensor 39 the fan 25 typically starts to operate. During actual operation of the drive engine 3, temperatures measured by the temperature sensor 39 may then be compared to such previously acquired reference signals and additionally it may be determined whether or not the fan 25 is operated, such determination being enabled due to the fluid flow sensor 9. Accordingly, for example in a case where an excessive temperature of the drive engine 3 is detected but no activation of the fan 25 is observed, it may be assumed that some defect or malfunction of the fan 25 has occurred.

(13) In contrast to conventional elevator systems in which no drive-engine-borne measurement instrument was provided for monitoring the fan's operation, the elevator system 100 with the drive engine arrangement 1 proposed herein enables, inter alia, a fine-tuning of a drive installation via sensor measurements. Furthermore, monitoring of the drive engine's fan during operation may be enabled without any human observer being necessary. The elevator system 100 proposed herein is ready for remote monitoring. Furthermore, the elevator system 100 and its drive engine arrangement 1 may be configurable in that feature computation from sensor raw signals may be changed “on-the-fly”, i.e. via software. As proposed herein, also existing elevator installations or third party drive engines may be monitored by attaching a sensor to the drive engine's fan.

(14) Finally, it should be noted that terms such as “comprising” do not exclude other elements or steps and terms such as “a” or “an” do not exclude a plurality. Also elements described in association with different embodiments may be combined.

(15) In accordance with the provisions of the patent statutes, the present invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from its spirit or scope.

LIST OF REFERENCE SIGNS

(16) 1 drive engine arrangement

(17) 3 drive engine

(18) 5 suspension traction means

(19) 7 elevator car

(20) 9 fluid flow sensor

(21) 11 traction sheave

(22) 13 housing of drive engine

(23) 14 rear side of housing

(24) 15 elevator control

(25) 17 counterweight

(26) 19 transmission line

(27) 21 transmission line

(28) 23 electric motor

(29) 25 fan

(30) 26 fan blade

(31) 27 fan motor

(32) 29 drive engine's power supply control

(33) 31 flap

(34) 33 switch

(35) 35 fluid flow through fan

(36) 37 fluid flow through sensor

(37) 39 temperature sensor

(38) 41 opening/slot

(39) 43 housing of fluid flow sensor

(40) 45 entrance side

(41) 100 elevator system

(42) 102 controller