JPS602587A - Controller for man conveyor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device for a passenger conveyor used for escalators, moving walkways, and the like.

BACKGROUND ART Passenger conveyors are used for escalators, moving walkways, and the like, and are widely used because they are suitable for continuously transporting large numbers of passengers. In this case, a three-phase induction motor is generally used as the drive device for the passenger conveyor, but this three-phase induction motor has low efficiency under light loads, and when the passenger conveyor is used in this light load state, The number is increasing.

To solve this problem, there is a system developed in Japanese Patent Application Laid-Open No. 5-11101 that detects the load and uses star connection when the load is light, and switches to delta connection when the load is heavy.
No. 7-141377.

However, in the control device for a passenger conveyor with the above configuration, when switching connections by detecting current as a load, the torque of the motor becomes significantly smaller than usual during star connection, so the power supply voltage There is a problem in that when the speed changes, the speed of the electric motor, that is, the speed of the passenger conveyor, changes significantly.

Therefore, an object of the present invention was to solve the above-mentioned problems, and to provide a control device for a passenger conveyor that increases efficiency during light loads and prevents speed changes due to power fluctuations. It is to be.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A man compare control device according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a circuit diagram showing an embodiment of a control device for a passenger conveyor according to the present invention. In the figure, 1 is a three-phase induction motor that drives the escalator, 2 is a relay for operating the escalator, and 2a to 2c are relays installed between the three-phase power supplies R, S, and T and the three-phase induction motor 1. 2 normally open contacts, 3
is a relay that operates the three-phase induction motor 1 as a star connection, and its normally open contacts 3a to 3c perform switching to the star connection. A relay 4 switches the connection of the three-phase induction motor 1 to a delta connection through its normally open contacts 4&-4c. Reference numeral 5 denotes a start switch for the escalator, which is connected between power lines via a stop switch 6 and a relay 2. 1 is a pulse generator connected to the rotating shaft of the three-phase induction motor 1,
Pulses with a period corresponding to the rotational speed of the electric motor are generated.

2d is a normally open contact of relay 2 connected in parallel to starting switch 5, and 8 is a pulse period detector with hysteresis characteristics between input and output, which detects the number of pulses within a predetermined time. When reaches P2, which corresponds to motor speed v2, an output is generated, and conversely, the speed decreases and motor speed ■1
It is set so that the output is cut off when P2 corresponding to P2 is reached. 9 is an output relay, and 10 is a timer for setting a suction time limit for starting the escalator, which is connected between power lines via a normally open contact 2e of the relay 2.

2f is a normally open contact of relay 2, normally open contact 108 of timer 10, normally closed contact 4d of relay 4, and relay 3.
Connected between the power lines via. 9a is contact 1
The normally open contact of the output relay 9 connected in parallel to 0a, and 10b are the normally open contacts of the timer 10, and the normally closed pull force 9b of the output relay 9, the normally open contact 3d of the relay 3, and the relay 4 are connected in parallel to each other. Connected between the power lines through.

FIG. 2 is a speed vs. torque characteristic diagram of the three-phase induction motor 1, where C8 is a speed vs. torque characteristic diagram when star connection is performed, and cd is a speed vs. torque characteristic diagram when delta connection is performed. FIG. 3 is a characteristic diagram showing the same speed vs. torque relationship, where C1 shows a case where the input voltage of the induction motor 1 decreases, and C2 shows a case where the input voltage increases.

In the device configured in this manner, to start the escalator, the start switch 5 is pressed to close it.

When the start switch 5 is closed, the power supply (+) - the start switch 5 - the stop switch 6 - the relay 2 - the power supply (-)
The circuit is configured and the relay 2 is excited. When the relay 2 is driven, its contacts 2a to 2f are closed. Here, when the contacts 2a to 2f are closed, three-phase power supplies R, S, and T are supplied to the three-phase induction motor 1. In this case, the relay 2 enters a self-holding state because its contact 2d closes due to the operation of the relay 2. When the contact 2f is closed, the relay 3 is excited, and when the contacts 3a to 3c are closed, the three-phase induction motor 1 is driven by star connection. still,
The timer 10 is energized by closing the contact 2e.

On the other hand, when the electric motor 1 rotates, the tacho generator T generates pulses proportional to the rotation speed. Then, when the motor 1 completes starting and reaches speed 2, the pulse period detector 8 outputs an output and energizes the output relay 9 in order for the pulse generator 7 to generate pulses of P2 every second. Then, when contact 9a of output relay 9 is closed and contact 9b is opened, power supply (+) - contact 2
Since the path f-contact 9a-contact 4d-relay 3-power supply (-) is formed and the relay 3 is energized, the motor 1 continues to operate with the star connection.

Next, when sufficient time has elapsed after contact 2e closes to complete startup, contact 10b of timer 10 closes, and contact 10
After the IL opens, the output relay 9 is activated according to the speed of the motor 1.
Depending on the operation, operation can be performed with star or delta connection.

Next, if the load increases or the power supply voltage decreases during operation and the speed of the induction motor 1 becomes less than v1, the pulse output pulse of the energizer 7 becomes less than pI H.
The output of the pulse period detector 8 disappears, the relay 9 is deenergized, contacts 9a open and contacts 9b are closed, and the relay 3 is deenergized and its contacts 3a to 3C are opened, so the induction motor 1 is temporarily turned off. disconnected from power supply. Also, contact point 3d
When the relay 4 is closed, a path of power supply (+) - contact 10b - contact 9b = contact 3dlJ relay 4 - power supply (-) is formed, and the relay 4 is energized. When the relay 4 is energized, the contacts 48~
4c is closed, the induction motor 1 is again connected to the power supply through delta connection and continues to operate.

Then, during operation under the above conditions, if the load decreases or the power supply voltage increases and the speed increases to 72 or more, the pulse generator T will correspondingly generate 22 or more pulses per second. When the input reaches 22 or more, the pulse period detector 8 energizes the output relay 9 to close its contacts 9& and open its contacts 9b. When the contact 9b is opened, the relay 4 is deenergized and the contacts 4a to 4c are opened, so that the induction motor 1 is temporarily disconnected from the power source. Also, close contact 4d, power supply (+) - contact 2f
- Contact 4d - Relay 3 - Power supply (-) circuit is closed,
Along with this, the relay 3 is energized, so that the induction motor 1 is connected to the power source in a star connection and continues to operate in the same way as in the case described above.

As explained above, according to the control device h for a passenger conveyor according to the present invention, since the motor connection is switched to star or delta depending on the speed of the three-phase induction motor, it is possible to handle light loads. Sometimes delta connections can also operate escalators at high rates.

In addition, in this invention, even if the power supply voltage drops during star connection, by appropriately selecting (1), the maximum torque will not be exceeded, and even if the power supply voltage becomes higher, Since there is no switching to delta mode even if the load reaches the expected load at normal voltage, it has the excellent effect of improving the efficiency of the passenger conveyor even over a wider load range.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of a control circuit for a passenger conveyor according to the present invention, and FIGS. 2 and 3 are speed and torque diagrams of an induction motor. 1...Three-phase induction motor, 2 .3.4.9...Relay, T...Pulse generator, 8...Pulse period detection G, 10...Timer. In the diagram, the same reference numerals indicate the same or equivalent parts. Agent Large Masuo Iwa (2 others) Mouth ＼＼＼＼ -L＼＼ Procedure sleeve correct answer ((spontaneous) Development I+ '6傅1-July 111'' 2. Name of invention Control system for passenger conveyor Stomach 3, Representative Katayuni of the person making the amendment Section 4, Agent 5, Subject of amendment (1) Column for detailed explanation of the invention in specification FF (2) Column for brief explanation of drawings in specification ν ( , 3) Drawing 6, contents of amendment (1) Specification sheet F, page 3, lines 5, 7, 8, 10
The words "relay" in the 14th and 18th rows are corrected to "contactor". (2) Page 4, lines 6, 8, 9, and 1 (). 14 lines [1 each has "relay"], and each line [1]
Correct with Funtafter-1. (3) Page 5, lines 5, 6, 7, and 10. In lines 1-1 of 12 and 13, the words ``relay'' are corrected to ``1 contactor.'' (4) On page 6, lines 6, 7, and 19, respectively [
The words sl/-j are respectively corrected to ``contactor''. (5) Same 17 ((3 I-chome, lines 3-4, line 4,
15th line 1], 123rd line IN, and 141st line, respectively, the words ``relay'' are corrected to ``1 contactor''. (6) On page 8, line 20, "2, 3. 4. 9... Relay-1, l" 2, 3. 4... Funtafter,
9...Relay" is corrected. (7) Correct side 1 fiSl and 1 as shown in the attached sheet. 7. Attached Majesties (1) Amended drawings 1 copy P! ward throat

Claims (1)

[Claims] (1) A three-phase induction motor that drives the passenger conveyor, a speed detection section that detects the speed of this three-phase induction motor, and a speed detection section that detects the speed of the induction motor according to the output of this speed detection section. A control device for a passenger conveyor, characterized in that it is equipped with a switching section for switching to.