JPH03143884A - Control circuit of elevator - 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 [Field of Industrial Application] The present invention relates to an elevator control circuit, and particularly to improving the safety of a brake circuit.

[Conventional technology]

In the conventional device, as described in Japanese Unexamined Patent Publication No. 54-72832, the magnetic brake is operated by the same contact 1, for example, the main contact and the auxiliary contact of a lift operation relay. However, if the elevator detects that the motor is not energized while the elevator is running and the lift operation relay is deenergized, the contacts become stiff or welded, causing the elevator to free run toward the heavier load, which is dangerous.

In other words, problems with contacts were not taken into consideration.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology does not take into account troubles such as stiffness and welding of the contactor contacts that open and close the brake circuit, and this poses a safety problem.

An object of the present invention is to provide an elevator control circuit that improves the safety of the brake circuit.

[Means for solving problems]

The above object is achieved by cutting the brake circuit in multiple stages using a plurality of contactors belonging to different circuits.

[Effect]

A plurality of contactors belonging to different circuits for opening and closing the brake coil each operate independently. As a result, even if the first-stage contactor contacts become stiff or welded, if the second-stage contactor contacts are normal, free running will not occur.

〔Example〕

Examples will be described below.

Figure 1 shows the system configuration of an inverter elevator.
FIG. 2 shows the control circuit.

The elevator power source 3φAC is supplied to the three-phase converter COv via the fuse free breaker FFB.

The power source converted to direct current by the three-phase converter COv is charged to the smoothing capacitor Ct via the rush current limiting resistor R1.

When a call occurs and a travel command is issued, the output buffer ZIOT of the travel contactor 10T shown in FIG. 2 becomes conductive and is controlled by a microcomputer. ) Traveling contactor 10T
The contact 10Tz short-circuits the inrush current limiting resistor R1 shown in FIG. 1, and a microcomputer (not shown) generates a speed command and a rotation direction signal. This signal becomes a drive command for the inverter INV, the inverter INV generates an output, the induction motor IM rotates, and the car C and the counterweight CW are driven via the reduction gear S directly connected to the induction motor IM. On the other hand, according to Figure 2,
When a brake release command is generated, the brake opening/closing output buffer 215B becomes conductive and the brake opening/closing contactor 15B is energized. 3φAC-FFB-transformer TR in Fig. 1
- Fuse F - Contact 10 Tz - Rectifier Si - Contact 15
The magnetic brake coil MgBrC is energized along the path B1-MgBr-8i, and the magnetic brake is in an open state.

The contacts Saz and Saz in FIG. 2 are the contacts of a safety relay, and the contact S a 11Sat opens when the safety switch is operated or a stop command is issued by the microcomputer. Thereby, the brake opening/closing contactor 15B,
The travel contactor 10T is deenergized, the NIL-Veta is stopped, and the brakes are applied.

Next, a case will be described in which a problem occurs in the contacts 15B1 of the brake opening/closing contactor 15B, such as welding, sticking, or bridging between the contacts. According to Figure 2, when there is a stop command,
Brake opening/closing output buffer Z15B becomes non-conductive,
Brake opening/closing contactor 15B is deenergized. In a normal state, the magnetic brake coil MgBrC is released and the brake is applied. However, since the contact 15B1 of the brake opening/closing contactor 15B is in trouble, the magnetic brake coil M g B r C remains energized. On the other hand, when there is no running command, the output buffer ZIOT of the running contactor IOT in FIG. 2 becomes non-conductive, and the running contactor IOT is deenergized.

Therefore, the magnetic brake coil MgBrC is deenergized by the contact point 10Tz of the traveling contactor IOT, and the brake can be applied. Traveling contactor IOT
The reason why the contact 10Tz is inserted between the transformer TR and the rectifier Si is that the breaking ability of the contact can be smaller if it is cut off on the AC side. Contact point 10 of traveling contactor IOT
If the breaking ability of Tz is sufficient, it is also possible to connect it in series with the contact 15B1 of the brake opening/closing contactor 1513 on the DC side of the rectifier Si.

Next, if a trouble occurs at the contact 10T2 of the travel contactor IOT, backup will be provided by the contact 15B1 of the brake opening/closing contactor 15B in the same manner as described above.

Next, a case where the (-) side in FIG. 2 is grounded will be described.

Even if one point is grounded on any circuit other than between the brake opening/closing contactor 15B and the output buffer 215B in the circuit of transformer taps 3 and 4, a short circuit current will flow at fuse F because the (-) side is grounded. It can protect the circuit. If one point ground occurs between the brake opening/closing contactor 15B and the output buffer 215B while the elevator is running, a stop command will be issued to the elevator, and even if the brake opening/closing output buffer 215B becomes electrically disconnected, the brake opening/closing contactor 15B will As the energization continues to be released, it becomes impossible to de-energize the magnetic brake coil MgBrC. In this case, when a stop command is issued to the elevator, the output buffer ZIOT of the running contactor
becomes non-conductive, and IOT in the circuit of transformer taps 5 and 6.
is deenergized and the contact 10T2 of the traveling contactor IOT is opened, so that the magnetic brake coil M g
It is possible to deenergize B r C and apply the brakes.

Next, when a single point ground occurs between the running contactor IOT and the output buffer ZIOT, this time backup is performed by the brake opening/closing contactor 15B, similarly to the above.

〔Effect of the invention〕

According to the present invention, the brake circuit is cut in two stages using different types of contactors, so even if a problem occurs with one contact, the brake can be reliably applied with the other contact, which has the effect of improving safety. be.

[Brief explanation of the drawing]

FIG. 1 shows a system configuration diagram of an inverter elevator according to an embodiment of the present invention, and FIG. 2 shows a control circuit diagram. 3φAC...Elevator power supply, CON...3
Phase converter, INV...Inverter, IOT...
Traveling contactor, 10 Tt, 10 T2... Contact of traveling contactor, ZIOT... Output buffer of traveling contactor, 15B... Brake opening/closing contactor,
z15B...output buffer of brake opening/closing contactor, MgBrC...magnetic brake coil, E...contact. Kayame Flash BrC-・Fu"net 7 Tobu L-Kikoi 2shi Kayagata

Claims (1)

[Claims] 1. A transformer is provided to generate various signals and control power from the elevator power source, a rectifier is connected to the secondary side of the transformer, and a magnetic brake coil of the elevator is connected to the output side of the rectifier. An elevator control circuit characterized in that a plurality of contacts belonging to different circuits for opening and closing the magnetic brake coil are connected in series to the magnetic brake coil, and the brake circuit is cut in multiple stages. 2. In claim 1 above, the plurality of contact contacts belonging to different circuits are a travel contact contact that is energized based on a travel command and a brake opening/closing contact contact that is energized based on a brake release command. An elevator control circuit characterized by being a contact point.