Sensor connecting unit, safety system and elevator

Patent metadata

Field	Value
Publication number	US-11242221-B2
Application number	US-201615270750-A
Country	US
Kind code	B2
Filing date	Sep 20, 2016
Priority date	Oct 7, 2015
Publication date	Feb 8, 2022
Grant date	Feb 8, 2022

Abstract

A sensor connecting unit includes a safety input for connecting with a sensor; a power supply that is controllable through a controllable power switch; and a first I/O processing unit and a second I/O processing unit being connected to each other through a reciprocal comparison communication channel. The first I/O processing unit and the second I/O processing unit are both connected through a measurement circuit to measure voltage, current or power between a reference input and the safety input, and connected to a safety bus. The first I/O processing unit informs the second I/O processing unit about switching off of the controllable power supply, the second I/O processing unit commands the first I/O processing unit to switch off the controllable power supply, and/or the second I/O processing unit measures an output of the controllable power switch to detect switching of the power switch.

First claim

The invention claimed is:

1. A sensor connecting unit, comprising:
a sensor connected between a safety input supply and a safety input, or, alternatively, a first sensor connected between the safety input supply and a first safety input and a second sensor connected between the safety input supply and a second safety input,
said sensor, or, alternatively, said first sensor and second sensor being safety sensor(s) installed in association with an elevator;
a power supply that is connected to the safety input supply and controllable through a controllable power switch, or, alternatively, a controllable power supply, the power supply or the controllable power supply being controllably supplying power to the sensor, or, alternatively, the first or second sensor, and switching off power from a power source to the sensor, or, alternatively, the first or second sensor;
a first I/O processing unit and a second I/O processing unit being connected to each other through a reciprocal comparison communication channel, and are connected to a safety bus; and
a first measurement circuit connected between the first I/O processing unit and the safety input, or alternatively, the first safety input, and a second measurement circuit connected between the second I/O processing unit and the safety input, or alternatively, the second safety input, the first and second measurement circuits being configured to measure voltage, current or power between a common ground and the safety input, or, alternatively between the common ground and the first and second safety input respectively,
wherein when the power supply or the controllable power supply is controllably switching off power from the power source to the sensor, or, alternatively, the first or second sensor, the first and second measurement circuits will not dissipate any power,
wherein the first I/O processing unit has been configured to control the controllable power switch or, alternatively, the controllable power supply for power supply of the sensor, or, alternatively, the first or second sensor, and
wherein operation includes:
i) the first I/O processing unit has been configured to inform the second I/O processing unit about switching of the power switch or, alternatively, of the controllable power supply for power supply of the sensor, or, alternatively, the first or second sensor, including said switching off of the power switch or, alternatively, of the controllable power supply, and
ii) the second I/O processing unit has been configured to command the first I/O processing unit to switch the power switch or, alternatively, of the controllable power supply for power supply of the sensor, or, alternatively, the first or second sensor, through the reciprocal comparison communication channel, including said switching off of the power switch or, alternatively, of the controllable power supply.

2. The sensor connecting unit according to claim 1 , wherein: the first I/O processing unit is configured to delay switching of the power switch or, alternatively, of the controllable power supply, for a predetermined period after informing the second I/O processing unit; or
the first I/O processing unit is configured to delay switching of the power switch or, alternatively, of the controllable power supply, for a predetermined period after having been commanded by the second I/O processing unit.

3. The sensor connecting unit according to claim 1 , wherein: the first I/O processing unit is configured to switch the controllable power switch on for 10 to 50 ms and then to switch the controllable power switch off.

4. The sensor connecting unit according to claim 1 , wherein: the first and second measurement circuits are configured to dissipate electric power form the power supply, or alternatively, from the controllable power supply, and/or to lead electric current to ground so that a voltage over the sensor, or, alternatively, the first or second sensor, is reduced in the first and second measurement circuits to a level accepted by an ADC line of the first I/O processing unit and of the second I/O processing unit.

5. The sensor connecting unit according to claim 4 , wherein: the voltage over the sensor, or, alternatively, the first or second sensor, is equal or greater than 9 V, whereas the voltage at the ADC line of the first I/O processing unit and of the second I/O processing unit is less than 5 V.

6. The sensor connecting unit according to claim 1 , wherein: the sensor, or, alternatively, the first or second sensor is a) a safety contact with at least one direct opening action contact, b) a safety switch with at least one safety output, or c) two or more non-safety switches.

7. The sensor connecting unit according to claim 1 , wherein: the first I/O processing unit has at least two off-time windows, a duration of which are different from each other, during which the power switch or, alternatively, the controllable power supply, is switched off.

8. The sensor connecting unit according to claim 1 , wherein: the safety sensor connecting unit is integrated in a safety logic unit.

9. The sensor connecting unit according to claim 1 , wherein:
the safety sensor connecting unit has been installed in a passenger and goods passenger lift, an inclined travel path lift, an escalator or a moving walk.

10. A safety system, comprising: a number of sensor connecting units according to claim 1 , and a number of safety logic units connected or connectable to the number of sensor connecting units locally and/or through a safety bus and having a first safety output and a second safety output.

11. The safety system according to claim 10 , wherein: the safety system has been installed in a passenger and goods passenger lift, an inclined travel path lift, an escalator or a moving walk.

12. An elevator, comprising:
an elevator car movable in a hoistway, the elevator car having at least one automatic or turnable car door;
a number of automatic or turnable hoistway doors; and
the safety system according to claim 10 and configured to control the safety of the at least one automatic or turnable car door and the number of hoistway doors.

13. The elevator according to claim 12 , wherein: the sensor connecting unit is configured to use a shorter off-time window to measure safety when the elevator is in normal operation mode and a longer off-time window when the elevator is in idle mode.

14. The sensor connecting unit according to claim 2 , wherein:
the first I/O processing unit is configured to switch the controllable power switch on for 10 to 50 ms and then to switch the controllable power switch off.

15. The sensor connecting unit according to any claim 2 , further comprising:
a sensor connected between a safety input supply and the safety input; or
a first sensor connected between the safety input supply and the first safety input and a second sensor connected between the safety input supply and the second safety input.

16. The sensor connecting unit according to claim 2 , further comprising:
a sensor connected between a safety input supply and the safety input; or
a first sensor connected between the safety input supply and the first safety input and a second sensor connected between the safety input supply and the second safety input.

17. The sensor connecting unit according to claim 1 , wherein the first I/O processing unit is configured to inform the second I/O processing unit about switching of the power switch or, alternatively, of the controllable power supply through the reciprocal comparison communication channel.

18. The sensor con

Assignees

• Kone Corp

Inventors

• Kattainen Ari
• Hovi Antti

Classifications

• G01R31/3271

  of high voltage or medium voltage devices (G01R31/333 takes precedence) · CPC title

• B66B13/22

  Operation of door or gate contacts · CPC title

• H01H47/002

  Monitoring or fail-safe circuits · CPC title

• B66B5/0031 Primary

  for safety reasons · CPC title

• B66B13/00

  Doors, gates, or other apparatus controlling access to, or exit from, cages or lift well landings (door fittings, locks E05) · CPC title