Forklift type AGV and braking system thereof

Abstract

The application discloses a forklift type AGV brake system, comprising a controller, a first contactor, a second contactor, a first pre-charge resistor connected in parallel with the first contactor, and a second pre-charge resistor connected in parallel with the second contactor. Through the redundant setting of the first contactor and the second contactor, when any one of the contactors has an abnormality such as contact sticking, the other contactor can still normally disconnect the connection between the power supply and the driving device, ensuring the effectiveness of the brake operation. Meanwhile, the pre-charge resistor is connected in parallel at both ends of the first contactor and the second contactor, so as to guarantee the safety of the circuit and the service life of the electrical components and improve the safety of the brake system. The application also discloses a forklift type AGV, which has the above beneficial effects.

Description

Technical Field

[0001] This application relates to the field of AGVs, and in particular to a forklift-type AGV and its braking system. Background Technology

[0002] With the development of AGVs, their safety performance has received increasing attention, and the braking system, as the execution part of all safety systems, is the most important component for both traditional forklifts and AGVs. Current AGV braking systems typically consist of two parts: an electromagnetic brake and a contactor. Once braking begins, the control circuit disconnects the power to the contactor coil, causing the contactor contacts to open, de-energizing the power cable connecting the contactor contacts, and completely de-energizing the motor, thus losing power. Simultaneously, the control circuit disconnects the power to the holding brake relay coil, causing the electromagnetic brake to de-energize and engage, thereby completing the braking process. Currently, conventional braking systems often only have one contactor connected to the drive unit, which is prone to contact sticking, leading to brake failure and affecting the operational safety of forklift-type AGVs.

[0003] Therefore, how to provide a solution to the above-mentioned technical problems is a problem that needs to be solved by those skilled in the art. Summary of the Invention

[0004] The purpose of this application is to provide a forklift-type AGV and its braking system, which can ensure the effectiveness of braking operation, while ensuring circuit safety and the service life of electrical components, thereby improving the safety of the braking system.

[0005] To address the aforementioned technical problems, this application provides a braking system for a forklift-type AGV, comprising a controller, a first contactor, a second contactor, a first pre-charge resistor connected in parallel with the first contactor, and a second pre-charge resistor connected in parallel with the second contactor, wherein:

[0006] The signal output terminal of the controller is connected to the first terminal of the coil of the first contactor and the first terminal of the coil of the second contactor respectively. The second terminal of the coil of the first contactor and the second terminal of the coil of the second contactor are both connected to the negative terminal of the system. The first terminal of the contact of the first contactor is connected to the power supply. The second terminal of the contact of the first contactor is connected to the first terminal of the contact of the second contactor. The second terminal of the contact of the second contactor is connected to the driving device.

[0007] The controller is used to output a braking signal to control the contacts of the first contactor and / or the contacts of the second contactor to disconnect when it is determined that the current operating condition meets the braking conditions.

[0008] Preferably, the braking system further includes:

[0009] The first arc extinguisher is connected in series with the first pre-charge resistor;

[0010] A second arc extinguisher connected in series with the second pre-charge resistor.

[0011] Preferably, the braking system of the forklift AGV further includes a first brake relay, a second brake relay, and a brake, wherein:

[0012] The signal output terminal of the controller is connected to the first terminal of the coil of the first brake relay and the first terminal of the coil of the second brake relay, respectively. The second terminals of the coils of the first and second brake relays are both connected to the negative terminal of the system. The moving terminal of the contact of the first brake relay is connected to the power supply. The first stationary terminal of the contact of the first brake relay is connected to the moving terminal of the contact of the second brake relay. The first stationary terminal of the second brake relay is connected to the first terminal of the brake. The second terminal of the brake is connected to the negative terminal of the system. The second stationary terminals of the contacts of the first and second brake relays are both left unconnected.

[0013] Preferably, the braking system further includes:

[0014] A third arc extinguisher, one end of which is connected to the moving end of the first brake relay and the other end of which is connected to the first stationary end of the first brake relay;

[0015] A fourth arc extinguisher, one end of which is connected to the moving end of the second brake relay and the other end of which is connected to the first stationary end of the second brake relay.

[0016] Preferably, the braking condition includes: detecting an obstacle signal output by the detection device.

[0017] Preferably, the braking condition includes: detecting a device malfunction signal.

[0018] Preferably, the braking system further includes:

[0019] A prompting device connected to the second end of the contact of the second contactor for indicating the contact status of the first contactor and / or the second contactor.

[0020] Preferably, the prompting device is an indicator light.

[0021] To address the aforementioned technical problems, this application also provides a forklift-type AGV, including a braking system for the forklift-type AGV as described in any of the above claims.

[0022] This application provides a braking system for a forklift-type AGV, including a controller, a first contactor, a second contactor, a first pre-charging resistor connected in parallel with the first contactor, and a second pre-charging resistor connected in parallel with the second contactor. Through the redundant arrangement of the first and second contactors, if either contactor experiences an abnormality such as contact sticking, the other contactor can still normally disconnect the connection between the power supply and the drive device, ensuring the effectiveness of the braking operation. Simultaneously, pre-charging resistors are connected in parallel across the first and second contactors to ensure circuit safety and extend the service life of electrical components, thereby improving the safety of the braking system. This application also provides a forklift-type AGV with the same beneficial effects as the aforementioned braking system. Attached Figure Description

[0023] To more clearly illustrate the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A schematic diagram of the braking system of a forklift AGV provided in this application;

[0025] Figure 2 This is a schematic diagram of the braking system of another forklift-type AGV provided in this application. Detailed Implementation

[0026] The core of this application is to provide a forklift-type AGV and its braking system, which can ensure the effectiveness of braking operation, while ensuring circuit safety and the service life of electrical components, thereby improving the safety of the braking system.

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the braking system of a forklift AGV provided in this application. The braking system of the forklift AGV includes a controller 1, a first contactor K1, a second contactor K2, a first pre-charge resistor R1 connected in parallel with the first contactor K1, and a second pre-charge resistor R2 connected in parallel with the second contactor K2, wherein:

[0029] The signal output terminal of controller 1 is connected to the first end of the coil of the first contactor K1 and the first end of the coil of the second contactor K2 respectively. The second ends of the coils of the first contactor K1 and the second ends of the coils of the second contactor K2 are both connected to the negative terminal of the system. The first end of the contact of the first contactor K1 is connected to the power supply. The second end of the contact of the first contactor K1 is connected to the first end of the contact of the second contactor K2. The second end of the contact of the second contactor K2 is connected to the driving device.

[0030] Controller 1 is used to output a braking signal to control the contacts of the first contactor K1 and / or the contacts of the second contactor K2 to open when it is determined that the current operating condition meets the braking conditions.

[0031] As a preferred embodiment, the braking system further includes:

[0032] The first arc extinguisher 21 is connected in series with the first pre-charge resistor R1;

[0033] The second arc extinguisher 22 is connected in series with the second pre-charge resistor R2.

[0034] Specifically, controller 1 is used to detect the current operating condition of the forklift AGV. If the current operating condition meets the braking conditions, a braking signal is generated. The braking conditions may include detecting an obstacle signal output by the detection device, detecting an equipment abnormality signal, or the current operating condition being an emergency stop braking condition. The detection device can specifically be a laser sensor, and the obstacle signal can specifically be the signal generated after the laser sensor detects an obstacle. In this embodiment, the first contactor K1 and the second contactor K2 are redundant, as shown in the reference... Figure 1 As shown, the coils of the first contactor K1 and the second contactor K2 are both connected to the signal output terminal of the controller 1. To improve safety, the first contactor K1 and the second contactor K2 can be normally open contactors. Correspondingly, when braking is not required, the controller 1 can generate a normal control signal. The normal control signal and the braking signal control the contacts of the contactors to perform different actions.

[0035] Taking the 01 signal as an example, the normal control signal is 1, and the braking signal is 0. When the controller 1 outputs 1, the coils of both the first contactor K1 and the second contactor K2 are energized, and the contacts of both contactors K1 and K2 are closed. At this time, power is supplied to the driver in the drive device through the power supply, thereby driving the motor to run. When the controller 1 outputs 0, the coils of both contactors K1 and K2 are de-energized, and the contacts of both contactors K1 and K2 are open, thereby cutting off the power supply path between the power supply and the drive device. With the structure of this application, when the first contactor K1 contact is abnormal, the second contactor K2 can still disconnect the power supply path between the power supply and the drive device after receiving the braking signal. Correspondingly, when the second contactor K2 contact is abnormal, the first contactor K1 can still disconnect the power supply path between the power supply and the drive device after receiving the braking signal, causing the motor to be completely de-energized, lose power, and complete braking. Therefore, the redundant electrical design of the two contactors can effectively prevent contact adhesion and equipment damage.

[0036] Furthermore, this application also includes a pre-charging resistor connected in parallel across each of the two contactors. This pre-charging resistor is used to slowly charge the capacitor during the initial high-voltage power-on phase of the vehicle. Without it, excessive current would break down the capacitor. Applying high voltage directly to the capacitor is equivalent to a momentary short circuit, and excessive short-circuit current can damage high-voltage electrical components. Therefore, this application incorporates a pre-charging resistor in the circuit design to ensure circuit safety. Types of pre-charging resistors include aluminum-cased resistors (also known as gold resistors), thermistors (PTC resistors), power resistors, and cement resistors (ceramic resistors), with aluminum-cased resistors being the most commonly used. The pre-charging resistor limits the magnitude of the current at the moment of power-on, preventing large currents from short-circuiting and damaging components, thus protecting the driver in the drive unit at the moment of power-on. This application also includes an arc extinguisher connected in parallel across each of the two contactors. The arc extinguisher and the pre-charging resistor are connected in series to prevent arcing and large currents from damaging electrical components, ensuring the service life of the electrical components.

[0037] This application provides a braking system for a forklift-type AGV, including a controller, a first contactor, a second contactor, a first pre-charging resistor connected in parallel with the first contactor, and a second pre-charging resistor connected in parallel with the second contactor. Through the redundant arrangement of the first and second contactors, if any one of the contactors malfunctions, such as contact sticking, the other contactor can still normally disconnect the connection between the power supply and the drive device, ensuring the effectiveness of the braking operation. At the same time, pre-charging resistors are connected in parallel at both ends of the first and second contactors to ensure circuit safety and the service life of electrical components, thereby improving the safety of the braking system.

[0038] Please refer to Figure 2 , Figure 2This is a schematic diagram of another braking system for a forklift AGV provided in this application, which is based on the above embodiment:

[0039] In a preferred embodiment, the braking system of the forklift AGV further includes a first brake relay K3, a second brake relay K4, and a brake 3, wherein:

[0040] The signal output terminal of controller 1 is connected to the first terminal of the coil of the first brake relay K3 and the first terminal of the coil of the second brake relay K4, respectively. The second terminals of the coils of the first brake relay K3 and the second terminal of the coil of the second brake relay K4 are both connected to the negative terminal of the system. The moving terminal of the contact of the first brake relay K3 is connected to the power supply. The first stationary terminal of the contact of the first brake relay K3 is connected to the moving terminal of the contact of the second brake relay K4. The first stationary terminal of the second brake relay K4 is connected to the first terminal of the brake 3. The second terminal of the brake 3 is connected to the negative terminal of the system. The second stationary terminals of the contacts of the first brake relay K3 and the second stationary terminals of the contacts of the second brake relay K4 are both left floating.

[0041] As a preferred embodiment, the braking system further includes:

[0042] A third arc extinguisher 23, one end of which is connected to the moving end of the first brake relay K3 and the other end of which is connected to the first stationary end of the first brake relay K3;

[0043] A fourth arc extinguisher 24, one end of which is connected to the moving end of the second brake relay K4, and the other end of which is connected to the first stationary end of the second brake relay K4.

[0044] Specifically, in this embodiment, the holding brake relay also adopts a redundant design, referring to... Figure 2 As shown, when the coil is de-energized, the moving end of the contact of the first brake relay K3 connects to its suspended stationary end. When the coil is energized, the moving end of the brake relay contact connects to its first stationary end. The same applies to the second brake relay K4. If either brake relay malfunctions, the other brake relay can de-energize and engage the brake 3, thus completing the braking process. Furthermore, arc extinguishers are installed at both ends of the first brake relay K3 and the second brake relay K4 to reduce the damage of electric arcs to the equipment, extend the service life of the electrical equipment, and ensure reliable operation of the electrical equipment. This makes the entire brake circuit dual-channel, improving the safety level of the braking system.

[0045] As a preferred embodiment, the braking system further includes:

[0046] A prompting device connected to the second end of the contact of the second contactor K2 for indicating the contact status of the first contactor K1 and / or the second contactor K2.

[0047] In a preferred embodiment, the prompting device is an indicator light.

[0048] Specifically, to further improve the reliability of the braking system, this application also includes a prompting device for detecting the contact status of the first contactor K1 and the second contactor K2. It is understood that when the contacts are closed, current will flow. A preset detection point can be established, and the prompting device detects the current at that point. Assuming the current controller 1 outputs a braking signal, if both the first contactor K1 and the second contactor K2 are in normal condition, then no current should flow through the detection point. In this case, the prompting device will display the first message. If current flows through the detection point, it indicates a contactor malfunction, and the prompting device will display the second message to remind the operator to take appropriate measures in a timely manner.

[0049] On the other hand, this application also provides a forklift AGV, including a braking system for a forklift AGV as described in any of the above.

[0050] For a description of the forklift-type AGV provided in this application, please refer to the above embodiments; further details will not be repeated here.

[0051] The forklift-type AGV provided in this application has the same beneficial effects as the braking system described above.

[0052] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0053] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A forklift AGV brake system, characterized by, The brake system comprises a controller, a first contactor, a second contactor, a first pre-charging resistor connected in parallel with the first contactor, and a second pre-charging resistor connected in parallel with the second contactor. The signal output end of the controller is connected with the first end of the coil of the first contactor and the first end of the coil of the second contactor respectively, the second end of the coil of the first contactor and the second end of the coil of the second contactor are connected with the system negative pole, the first end of the contact of the first contactor is connected with the power supply, the second end of the contact of the first contactor is connected with the first end of the contact of the second contactor, the second end of the contact of the second contactor is connected with the driving device; the brake system further comprises a first arc extinguisher connected in series with the first pre-charging resistor, and a second arc extinguisher connected in series with the second pre-charging resistor. The working process is as follows: the normal control signal is 1, and the brake signal is 0; when the output of the controller is 1, the coils of the first contactor and the second contactor are powered, and the contacts of the first contactor and the second contactor are closed, at this time, the power supply supplies power to the driver in the driving device, so as to drive the motor to run; when the output of the controller is 0, the coils of the first contactor and the second contactor are powered off, and the contacts of the first contactor and the second contactor are disconnected, so as to cut off the power supply path between the power supply and the driving device; when the contact of the first contactor is abnormal, the second contactor can still disconnect the power supply path between the power supply and the driving device after receiving the brake signal, and correspondingly, when the contact of the second contactor is abnormal, the first contactor can still disconnect the power supply path between the power supply and the driving device after receiving the brake signal; The controller is used for outputting a brake signal to control the contact of the first contactor and / or the contact of the second contactor to be disconnected when it is determined that the current running condition meets the brake condition. The brake system of the fork truck type AGV further comprises a first brake relay, a second brake relay, and a brake. The signal output end of the controller is connected with the first end of the coil of the first brake relay and the first end of the coil of the second brake relay respectively, the second end of the coil of the first brake relay and the second end of the coil of the second brake relay are connected with the system negative pole, the movable end of the contact of the first brake relay is connected with the power supply, the first fixed end of the contact of the first brake relay is connected with the movable end of the contact of the second brake relay, the first fixed end of the contact of the second brake relay is connected with the first end of the brake, the second end of the brake is connected with the system negative pole, the second fixed end of the contact of the first brake relay and the second fixed end of the contact of the second brake relay are both provided in a suspended manner, and the brake system further comprises a third arc extinguisher having one end connected with the movable end of the first brake relay and the other end connected with the first fixed end of the first brake relay, and a fourth arc extinguisher having one end connected with the movable end of the second brake relay and the other end connected with the first fixed end of the second brake relay. When the coil is powered off, the moving end of the contact of the first latching relay is connected with the suspended fixed end thereof, and when the coil is powered on, the moving end of the contact of the first latching relay is connected with the first fixed end thereof; the second latching relay is the same, and when any one of the latching relays is abnormal, the other latching relay can control the brake to be powered off and latched, so as to complete braking.

2. The braking system of the fork truck AGV according to claim 1, characterized by, The braking condition comprises detecting an obstacle signal output by the detection device.

3. The braking system of the fork truck AGV according to claim 1, characterized by, The braking condition comprises detecting an abnormal signal of the device.

4. The braking system of a fork truck type AGV according to any one of claims 1 to 3, characterized in that, The braking system further comprises: a prompt device connected with the second end of the contact of the second contactor and used for indicating the contact state of the first contactor and / or the second contactor.

5. The braking system of a fork truck AGV according to claim 4, wherein The prompt device is an indicator.

6. A fork truck AGV characterized by comprising: A braking system of a forklift AGV, comprising the braking system according to any one of claims 1-5.

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