PASSENGER CONVEYOR WITH DEEP SLEEP MODE

Abstract

The invention relates to a passenger conveyor, e.g. an elevator, comprising a conveyor motor being controlled by a conveyor control via a motor drive, the motor drive comprising a frequency converter with a rectifier bridge, an intermediate DC circuit and a converter bridge connected with the conveyor motor. The rectifier bridge is configured to be connected to mains via at least one relay, which relay is controlled by the conveyor control, the conveyor comprises a deep sleep mode, in which the frequency converter as well as at least a major part of conveyor control is switched off,

in which conveyor the intermediate DC circuit forms the power supply for the conveyor control. During the activation of the deep sleep mode the conveyor control is configured to open the relay, whereby at least one signal circuit of the conveyor is configured to remain powered at least during the deep sleep mode. The conveyor comprises a wake-up circuit which is connected to the signal circuit and which is configured to be permanently powered at least during the deep sleep mode, which wake-up circuit is configured to close the relay dependent on a signal received from the signal circuit.

Claims

1. Passenger conveyor comprising a conveyor motor being controlled by a conveyor control via a motor drive, the motor drive comprising a frequency converter with a rectifier bridge, an intermediate DC circuit and a converter bridge connected with the conveyor motor, whereby the rectifier bridge is configured to be connected to mains via at least one relay, which relay is controlled by the conveyor control, the conveyor comprises a deep sleep mode, in which the frequency converter as well as at least a major part of conveyor control is switched off, in which conveyor the intermediate DC circuit forms the power supply for the conveyor control, whereby during the activation of the deep sleep mode the conveyor control is configured to open the relay, whereby at least one signal circuit of the conveyor is configured to remain powered at least during the deep sleep mode, and whereby the conveyor comprises a wake-up circuit which is connected to the signal circuit and which is configured to be permanently powered at least during the deep sleep mode, which wake-up circuit is configured to close the relay dependent on a signal received from the signal circuit.

2. Passenger conveyor according to claim 1, comprising two parallel relays, i.e. one main relay and one charging relay, which charging relay being configured to charge any capacitors or batteries located in the intermediate DC circuit and which charging relay comprises at least one current limiting component connected to a corresponding charging relay switch, whereby during the activation of the deep sleep mode the conveyor control is configured to open the main relay as well as the charging relay, in which conveyor the wake-up circuit is configured to close the charging relay dependent on a signal from the signal circuit.

3. Passenger conveyor according to claim 2, wherein the conveyor control is configured to automatically re-start and to close the main relay after the charging relay is closed.

4. Passenger conveyor according to claim 2, wherein the current limiting component is a PTC thermistor connected in series with the charging relay switch.

5. Passenger conveyor according to claim 1, wherein the wake-up circuit comprises a power supply.

6. Passenger conveyor according to claim 5, wherein the power supply is a transformer connected to mains.

7. Passenger conveyor according to claim 6, wherein the transformer has a power consumption of less than 10 W, preferably less than 5 W, most preferably less than 1 W.

8. Passenger conveyor according to claim 1, wherein the signal circuit is connected to any call giving devices of the conveyor.

9. Passenger conveyor according to claim 1, wherein the signal circuit is connected to a remote monitoring center of the conveyor.

10. Passenger conveyor according to claim 1, wherein the signal circuit is connected with an internal and/or external signal issuing means.

11. Passenger conveyor according to claim 1, wherein the conveyor control is configured to activate the deep sleep mode after no call has been issued for a predetermined time period.

12. Passenger conveyor according to claim 1, wherein the conveyor control is configured to activate the deep sleep mode dependent on the prevailing time.

13. Passenger conveyor according to claim 1, wherein the charging relay is connected in parallel to the main relay.

14. Method for operating a passenger conveyor having a conveyor control comprising a deep sleep mode wherein the power supply of the conveyor control and of a motor drive of an conveyor motor is switched off, whereby the motor drive comprises a frequency converter with a rectifier bridge, an intermediate DC circuit and a converter bridge connected with the conveyor motor, whereby the rectifier bridge is connected to mains via a relay, which relay is controlled by the conveyor control, whereby the intermediate DC circuit forms the power supply for at least a major part ofpreferably the completeconveyor control, whereby during the activation of the deep sleep mode the relay is opened and at least one signal circuit of the conveyor is remained powered, and whereby upon receipt of a wake-up signal received from the signal circuit, the intermediate DC circuit is charged up again by closing the relay, causing the conveyor control to re-start operation.

15. Method according to claim 14, wherein upon receipt of a wake-up signal received from the signal circuit, the intermediate DC circuit is charged up again by closing a charging relay which comprises a current limiting component, and that after the charging up of the intermediate DC circuit the conveyor control is automatically restarted and initiated to close a main relay connecting the rectifier bridge with mains.

16. Method according to claim 14, wherein a wake-up signal is generated in case a call being issued by any call giving device, a remote monitoring signal is received, a monitoring circuit issues an operation anomaly signal.

Description

[0028] The invention is now described schematically in a preferred embodiment in connection with the figures. In the figures

[0029] FIG. 1 shows a schematic diagram of an inventive elevator, and

[0030] FIG. 2 shows a relay between mains and the rectifier bridge of a frequency converter having a parallel main relay and charging relay.

[0031] The elevator 10 comprises an elevator control 12, a motor drive 14, an elevator motor 16, optionally with a traction sheave 18 driving an elevator car 20 as well as optionally a counter weight 22 via elevator ropes 24. The motor drive 14 is connected to mains 26 via a relay 28 which is controlled by the elevator control 12 via relay control line 30. The motor drive 14 comprises a rectifier bridge 32, an intermediate DC circuit 34 with a capacitor 36 located between the positive and negative branch of the DC circuit as well as a converter bridge 38 connected with the elevator motor 16. The intermediate DC circuit 34 is connected with the elevator control 12 via supply lines 40 which form the power supply for the elevator control 12. On the other hand, the elevator control 12 controls the semiconductor switches of the converter bridge 38 of the motor drive 14. The motor drive 14 may be a regenerative motor drive, in which case rectifier bridge 32 may be configured to regenerate energy from the DC intermediate circuit back to the mains. The elevator 10 further comprises a signal circuit 42 which is connected with a monitoring circuit 44 in the elevator control 12, with internet 46 to be able to be contacted by a remote monitoring center, as well as with internal or external signal issuing means 48, for example monitoring means or a clock circuit. The most essential connection of the signal circuit 42 is to any call giving device 50 as e.g. car call panels and floor call panels in the elevator 10. These call giving devices 50 may comprise push buttons 52 as well as contactless call giving devices, for example via RFID or any other transmitter devices. The elevator further comprises a wake-up circuit 60 comprising a transformer 62 connected to mains 26 as well as a wake-up control 64 connected to the transformer 62. The wake-up control 64 is also connected via a signal control line 66 with the signal circuit 42 to receive wake-up signals via wake-up signal line 66 from the signal circuit 42. The wake-up control 64 is further connected to the relay 28 via the relay control line 68.

[0032] The elevator control 12 comprises an automatic start module 70 which is activated during re-start of the elevator control 12 and initiates automatic start of the elevator control 12 after power-up of the intermediate DC circuit 34.

[0033] The invention works as follows:

[0034] In certain cases, for example after a certain time period of inactivity, for example after 15 or 30 minutes of inactivity, the elevator control 12 initiates a deep sleep mode via the relay control line 30, disconnecting the relay 28 whereby the motor drive 14 is de-energized. This also leads to the loss of the power supply for the elevator control 12 via the supply lines 40. Still active in deep-sleep mode are the signal circuit 42 as well as the wake-up circuit 60 which are preferably always running. When the signal circuit 42 gets a signal from any of the signal issuing components as e.g. monitoring circuit 44, internet 46, external signal issuing devices 48 or call giving devices 50 via call buttons 52 or wireless ID readers (not shown), it issues via the wake-up signal line 66 a wake-up signal to the wake-up control 64 which then initiates the relay 28 via the wake-up control line 68 to close the relay 28. The closing of the relay 28 leads to the power-up of the intermediate DC circuit 34 so that the elevator control again receives power via the supply lines 40. In this case, the automatic starting module 70 of the elevator control automatically initiates the elevator control to restart its operation.

[0035] FIG. 2 shows a different embodiment of a relay 28 which has the reference number 80. The relay 80 comprises a parallel connection of a main relay 82 with main switches 83 for each phase and a charging relay 84 which comprises a series connection of a PTC resistor 86 and a corresponding charging relay switch 88. The invention works as follows. In case the elevator control 12 activates the deep sleep mode it initiates the main relay 82 as well as the charging relay 84 to open the corresponding relay switches 83, 88.

[0036] As mentioned above, in the deep sleep mode, both relays are open so that the frequency converter is completely switched off. In case the wake-up circuit 60 receives a wake-up signal via the wake-up signal line 66 from the signal circuit 42, it controls via the wake-up control line 68 the charging relay 84 to close the corresponding relay switches 88. This leads to a re-charging of the capacitor 36 in the intermediate DC circuit with a limited current resulting in the voltage of the intermediate DC circuit rising. This leads to the supply of energy via the supply lines 40 to the elevator control 12 whereafter the automatic starting module 70 of the elevator control 12 initiates the main relay 82 to close so that now the frequency converter or motor bridge 14 is again fully connected to mains 26. In practice, a motor control part of elevator control 12 sets a control signal that closes the main relay 82. In this connection it is to remark that the switches 83 of the main relay are heavy duty switches (e.g. relays or contactors) which are able to transfer high currents. The switches 88 of the charging relay are essentially smaller and are only intended to reload the capacitor 36 in the intermediate DC circuit with a comparably low current.

[0037] In the most preferred embodiment the wake-up circuit 60 is located inside the motor drive 14 (frequency converter). The signal circuit 42 is preferably located inside of the elevator control 12. A motor control part of the elevator control 12 is located inside the motor drive 14, and it controls the semiconductor switches of the converter bridge 38 of the motor drive 14. Other parts of elevator control 12, such as processing of elevator calls, are located in the elevator control unit.

[0038] In practice, the signal line 66 goes from the signal circuit 42 to the wake up circuit 60 of the frequency converter 14 as a serial data signal line, such that frequency converter 14 wakes up when any kind of data stream/pulse sequence e.g. of a minimum length is sent to the wake up circuit 64. After wake up, the very same signal line 66 is used for data communication between the elevator control 12 and the frequency converter 14. This has the advantage that no extra signal lines are required between the frequency converter 14 and the elevator control 12 for this deep sleep mode implementation, such that no changes are required for the existing signal interfaces.

[0039] In the most preferred embodiment, in the deep sleep mode every component inside the frequency converter 14 except the wake-up circuit 60 is turned off. This way the energy saving effect is as high as possible.

[0040] The described embodiments should not be regarded as delimiting the present invention which is defined by the appended patent claims.

REFERENCE LIST

[0041] 10 elevator [0042] 12 elevator control [0043] 14 motor drive [0044] 16 elevator motor [0045] 18 traction sheave [0046] 20 elevator car [0047] 22 counterweight [0048] 24 elevator ropes [0049] 26 mainspublic three phase AC network [0050] 28 relay [0051] 30 relay control line [0052] 32 rectifier bridge [0053] 34 intermediate DC circuitDC link [0054] 36 capacitor [0055] 38 converter bridge [0056] 40 supply lines [0057] 42 signal circuit [0058] 44 monitoring circuit [0059] 46 internet [0060] 48 external signal issuing device [0061] 50 call giving device [0062] 52 car call buttonshall call buttons [0063] 60 wake-up circuit [0064] 62 transformerlow power transformer [0065] 64 wake-up control [0066] 66 wake-up signal line [0067] 68 wake-up control line [0068] 70 automatic starting module of the elevator control [0069] 80 relay (second embodiment) [0070] 82 main relay [0071] 83 main relay switch [0072] 84 charging relay [0073] 85 charging circuit [0074] 86 PTC resistorvaristor [0075] 88 charging relay switch