Control unit for people and goods rack and pinion lift with double programmable PLC

Abstract

The utility model discloses a kind of people and goods dual-purpose rack lifting elevator control unit with double programmable PLC, belong to elevator control field.The control unit includes the power box being arranged in hoistway first floor and the control box being arranged on car, and first programmable PLC and second programmable PLC are respectively arranged in power box and control box.First programmable PLC is responsible for processing landing call and display signal, and second programmable PLC is responsible for processing car limit signal and drive control.Two programmable PLCs are only through a two-core communication line to carry out signal transmission and interaction, replace traditional multi-core control cable.The utility model greatly simplifies system wiring, reduces cost and failure rate, while improving the reliability and functionality of control system.

Description

Technical Field

[0001] This utility model belongs to the field of elevator control, specifically relating to a rack and pinion elevator control unit with dual programmable PLCs for both people and goods. Background Technology

[0002] An elevator is a fixed lifting device that serves designated floors and is widely used in docks, power plants, construction sites, and other locations. It consists of a car that runs on standard sections, and the car's size and structure facilitate passenger access and loading / unloading of goods.

[0003] See Figure 1 As shown, traditional elevators mostly use relay control systems, which suffer from high failure rates and inconvenient maintenance. More importantly, their control signal transmission relies primarily on multi-core traveling cables between the power supply box and the control cabinet. For example, dockside elevators typically require up to 48 cores of cable to power the car and transmit control signals. These multi-core cables are expensive, heavy, and prone to wear, and the numerous cores make troubleshooting difficult, thus limiting system reliability. Utility Model Content

[0004] This invention aims to overcome the shortcomings of existing technologies by providing a rack and pinion elevator control unit with dual programmable PLCs for both passenger and freight transport. This control unit can solve problems such as complex control systems, high failure rates, inconvenient maintenance, and poor reliability.

[0005] To solve the above-mentioned technical problems, this utility model is implemented as follows: A rack and pinion elevator control unit with dual programmable PLCs for both people and goods is characterized in that it includes a first programmable PLC and a second programmable PLC; The first programmable PLC is installed in a power supply box at a fixed position in the shaft. The second programmable PLC is installed in the elevator car and moves with it in the car control box; The signal transmission port of the first programmable PLC is connected to the signal transmission port of the second programmable PLC via a two-core communication line; the two-core communication line is used to realize bidirectional signal transmission and control coordination between the first programmable PLC and the second programmable PLC.

[0006] Furthermore, the first programmable PLC is configured to receive and process call signals and floor display signals from each floor of the elevator; the second programmable PLC is configured to receive and process signals from the upper limit switch of the car, and control the frequency converter and motor that drive the elevator.

[0007] Furthermore, the communication line adopts the fieldbus protocol of the RS-485 electrical standard.

[0008] Compared with the prior art, this utility model has the following characteristics: 1. This utility model utilizes dual programmable PLC distributed control, which can replace the traditional multi-core control cable with a communication cable that only requires two cores, significantly saving cable costs and reducing the weight and volume of the accompanying cable.

[0009] 2. This invention overcomes the shortcomings of high failure rate and inconvenient maintenance in relay control systems. At the same time, the reduction in communication wire cores directly reduces the risk of system downtime due to wire core failures.

[0010] 3. The two programmable PLCs of this utility model each perform their own functions and work together to handle more complex control logic and realize more functions. At the same time, reliable communication ensures the safe operation of the entire system. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of a traditional control unit structure; Figure 2 This is a schematic diagram of the control system of this utility model.

[0012] In the diagram: 1. 12-core communication cable; 2. PLC control box; 3. Motor; 4. Limit switch; 5. Elevator car; 6. Frequency converter; 7. Cable trolley; 8. Pit; 9. Floor call button; 10. Second programmable PLC; 11. Two-core communication cable; 12. First programmable PLC; 13. Terminal block. Detailed Implementation

[0013] The present invention will now be described in detail through specific embodiments. These embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art. As used throughout the specification and claims, the terms "comprising" or "including" are open-ended and are interpreted as "comprising but not limited to". The following description describes preferred embodiments of the present invention; however, this description is intended to illustrate the general principles of the specification and is not intended to limit the scope of the present invention. The scope of protection of the present invention shall be determined by the appended claims.

[0014] like Figure 2 As shown, the main function of the control unit of this utility model is to distribute the control function to two nodes. It is fixedly installed in a power supply box on the first (or bottom) floor of the shaft, and integrates the first programmable PLC12 (see...). Figure 2 As shown, a Siemens S7-200 series is used. This first programmable PLC12 acts as the dispatch center, responsible for collecting command signals from the call buttons on each floor of the building and managing the floor display information.

[0015] The control box inside the elevator car 5, which moves up and down with the elevator car 5, integrates a second programmable PLC 10 (see...). Figure 2 As shown, a Siemens S7-200 series can be used. The second programmable PLC 10 serves as the execution unit and is directly connected to the equipment on the car, including but not limited to: limit switches 4 for detecting the car position, frequency converter 6 for controlling the speed and direction of motor 3, and motor 3 for driving the elevator.

[0016] In this invention, the first programmable PLC 12 and the second programmable PLC 10 establish a communication connection via a two-core communication line. This communication line uses industrial fieldbus protocols such as RS-485 to achieve high-speed and reliable data exchange between the two programmable PLCs. The first programmable PLC 12 sends the received "up or down" call signal for the floor where the elevator car is located to the second programmable PLC 10 via the two-core communication line 11. The second programmable PLC 10, based on this signal and the current car position (provided by the limit switch 4), controls the motor 3 via the frequency converter 6 until the car smoothly arrives at the floor. Simultaneously, it feeds back the real-time car position information to the first programmable PLC 12 for updating the floor display. Through this structural design, the control signals that originally required parallel transmission through dozens of wires are converted into data packets transmitted serially between the first programmable PLC 12 and the second programmable PLC 10 via the two-core communication line. This not only greatly simplifies the physical wiring, but also leaves room for the expansion of system functions. New control logic can be implemented simply by modifying the control programs of the first programmable PLC12 and the second programmable PLC10, without changing the hardware wiring.

[0017] The content of this utility model is not limited to the embodiments listed. Any equivalent modifications made by those skilled in the art to the technical solution of this utility model after reading this utility model specification shall be covered by the claims of this utility model.

Claims

1. A control unit for a rack and pinion elevator with dual programmable PLCs for both passenger and freight transport, characterized in that, include: First programmable PLC (12) and second programmable PLC (10); The first programmable PLC (12) is installed in a power supply box at a fixed position in the shaft; The second programmable PLC (10) is installed in the elevator car (5) and moves with it in the car control box; The signal transmission port of the first programmable PLC (12) is connected to the signal transmission port of the second programmable PLC (10) via a two-core communication line (11); the two-core communication line (11) is used to realize bidirectional signal transmission and control coordination between the first programmable PLC (12) and the second programmable PLC (10).

2. The rack and pinion elevator control unit with dual programmable PLCs for both people and goods as described in claim 1, characterized in that, The first programmable PLC (12) is configured to receive and process call signals and floor display signals from each floor of the elevator; the second programmable PLC (10) is configured to receive and process the signal from the upper limit switch (4) of the car, and control the frequency converter (6) and motor (3) that drive the elevator.

3. The rack and pinion elevator control unit with dual programmable PLCs for both passenger and freight transport as described in claim 1 or 2, characterized in that, The communication line uses the RS-485 electrical standard fieldbus protocol.

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